diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackSpeedModifierImpl.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackSpeedModifierImpl.java
new file mode 100644
index 0000000..30eae2c
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackSpeedModifierImpl.java
@@ -0,0 +1,39 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier;
+
+import com.mojang.serialization.Codec;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.anim.property.AnimationProperty.PlaybackSpeedModifier;
+import com.tiedup.remake.rig.anim.types.DynamicAnimation;
+import com.tiedup.remake.rig.patch.LivingEntityPatch;
+
+/**
+ * Phase 3 D1 — data-driven concrete implementation of
+ * {@link PlaybackSpeedModifier}. The base functional interface takes five
+ * parameters ; datapack authors never need all of them, so concrete impls
+ * ignore the irrelevant ones.
+ *
+ * <p>JSON schema :
+ * <pre>{@code
+ *   "play_speed_modifier": { "type": "tiedup:constant_factor", "factor": 0.5 }
+ * }</pre>
+ *
+ * <p>Consumer : {@link com.tiedup.remake.rig.anim.AnimationPlayer#tick} reads
+ * the modifier and multiplies the current {@code playbackSpeed} by whatever
+ * the modifier returns each tick — so a modifier that returns {@code 0.5F}
+ * halves the animation speed.
+ */
+public interface PlaybackSpeedModifierImpl extends PlaybackSpeedModifier {
+
+	Codec<PlaybackSpeedModifierImpl> CODEC = PlaybackSpeedModifierRegistry.dispatchCodec();
+
+	ResourceLocation type();
+
+	@Override
+	float modify(DynamicAnimation self, LivingEntityPatch<?> entitypatch, float speed, float prevElapsedTime, float elapsedTime);
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackSpeedModifierRegistry.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackSpeedModifierRegistry.java
new file mode 100644
index 0000000..ac79b8e
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackSpeedModifierRegistry.java
@@ -0,0 +1,70 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.DataResult;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.anim.modifier.impl.ConstantFactorSpeedModifier;
+import com.tiedup.remake.rig.anim.modifier.impl.LinearRampSpeedModifier;
+
+/**
+ * Registry of {@link PlaybackSpeedModifierImpl} type ids → codecs. Same
+ * dispatch pattern as {@link PoseModifierRegistry}.
+ *
+ * <p>Base impls :
+ * <ul>
+ *   <li>{@code tiedup:constant_factor} — multiply speed by a fixed factor</li>
+ *   <li>{@code tiedup:linear_ramp} — linear interpolation between a start and
+ *       end factor over {@code elapsedTime} from 0 to {@code duration}</li>
+ * </ul>
+ */
+public final class PlaybackSpeedModifierRegistry {
+
+	private static final Map<ResourceLocation, Codec<? extends PlaybackSpeedModifierImpl>> TYPES = new HashMap<>();
+
+	private PlaybackSpeedModifierRegistry() {}
+
+	public static <T extends PlaybackSpeedModifierImpl> void register(ResourceLocation id, Codec<T> codec) {
+		if (TYPES.containsKey(id)) {
+			throw new IllegalStateException("Playback speed modifier type " + id + " is already registered.");
+		}
+
+		TYPES.put(id, codec);
+	}
+
+	public static Map<ResourceLocation, Codec<? extends PlaybackSpeedModifierImpl>> types() {
+		return Collections.unmodifiableMap(TYPES);
+	}
+
+	public static Codec<? extends PlaybackSpeedModifierImpl> getCodec(ResourceLocation id) {
+		return TYPES.get(id);
+	}
+
+	public static Codec<PlaybackSpeedModifierImpl> dispatchCodec() {
+		return ResourceLocation.CODEC.partialDispatch(
+			"type",
+			mod -> DataResult.success(mod.type()),
+			id -> {
+				Codec<? extends PlaybackSpeedModifierImpl> codec = TYPES.get(id);
+				if (codec == null) {
+					return DataResult.error(() -> "Unknown playback speed modifier type: " + id);
+				}
+				return DataResult.success(codec);
+			}
+		);
+	}
+
+	static {
+		register(ConstantFactorSpeedModifier.ID, ConstantFactorSpeedModifier.CODEC);
+		register(LinearRampSpeedModifier.ID, LinearRampSpeedModifier.CODEC);
+	}
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackTimeModifierImpl.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackTimeModifierImpl.java
new file mode 100644
index 0000000..d391ebd
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackTimeModifierImpl.java
@@ -0,0 +1,37 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier;
+
+import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.Codec;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.anim.property.AnimationProperty.PlaybackTimeModifier;
+import com.tiedup.remake.rig.anim.types.DynamicAnimation;
+import com.tiedup.remake.rig.patch.LivingEntityPatch;
+
+/**
+ * Phase 3 D1 — data-driven concrete implementation of
+ * {@link PlaybackTimeModifier}. The base interface returns a
+ * {@code Pair<Float, Float>} of {@code (prevElapsed, elapsed)}, typically used
+ * to loop a sub-section of an animation (set {@code elapsed} back to the
+ * looppoint when it crosses a threshold).
+ *
+ * <p>JSON schema :
+ * <pre>{@code
+ *   "elapsed_time_modifier": { "type": "tiedup:loop_section",
+ *                               "loop_start": 0.3, "loop_end": 0.8 }
+ * }</pre>
+ */
+public interface PlaybackTimeModifierImpl extends PlaybackTimeModifier {
+
+	Codec<PlaybackTimeModifierImpl> CODEC = PlaybackTimeModifierRegistry.dispatchCodec();
+
+	ResourceLocation type();
+
+	@Override
+	Pair<Float, Float> modify(DynamicAnimation self, LivingEntityPatch<?> entitypatch, float speed, float prevElapsedTime, float elapsedTime);
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackTimeModifierRegistry.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackTimeModifierRegistry.java
new file mode 100644
index 0000000..1a8da04
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/PlaybackTimeModifierRegistry.java
@@ -0,0 +1,70 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.DataResult;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.anim.modifier.impl.LoopSectionTimeModifier;
+
+/**
+ * Registry of {@link PlaybackTimeModifierImpl} type ids → codecs.
+ *
+ * <p>One base impl today :
+ * <ul>
+ *   <li>{@code tiedup:loop_section} — rewind elapsed time back to a loop
+ *       start when it crosses a loop end threshold</li>
+ * </ul>
+ *
+ * <p>Not a ton of base impls because the common «replay this window»
+ * behaviour is what 95% of bondage loops need ; more exotic time warps
+ * (ping-pong, jitter) can be added later without a schema break.
+ */
+public final class PlaybackTimeModifierRegistry {
+
+	private static final Map<ResourceLocation, Codec<? extends PlaybackTimeModifierImpl>> TYPES = new HashMap<>();
+
+	private PlaybackTimeModifierRegistry() {}
+
+	public static <T extends PlaybackTimeModifierImpl> void register(ResourceLocation id, Codec<T> codec) {
+		if (TYPES.containsKey(id)) {
+			throw new IllegalStateException("Playback time modifier type " + id + " is already registered.");
+		}
+
+		TYPES.put(id, codec);
+	}
+
+	public static Map<ResourceLocation, Codec<? extends PlaybackTimeModifierImpl>> types() {
+		return Collections.unmodifiableMap(TYPES);
+	}
+
+	public static Codec<? extends PlaybackTimeModifierImpl> getCodec(ResourceLocation id) {
+		return TYPES.get(id);
+	}
+
+	public static Codec<PlaybackTimeModifierImpl> dispatchCodec() {
+		return ResourceLocation.CODEC.partialDispatch(
+			"type",
+			mod -> DataResult.success(mod.type()),
+			id -> {
+				Codec<? extends PlaybackTimeModifierImpl> codec = TYPES.get(id);
+				if (codec == null) {
+					return DataResult.error(() -> "Unknown playback time modifier type: " + id);
+				}
+				return DataResult.success(codec);
+			}
+		);
+	}
+
+	static {
+		register(LoopSectionTimeModifier.ID, LoopSectionTimeModifier.CODEC);
+	}
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/PoseModifierImpl.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/PoseModifierImpl.java
new file mode 100644
index 0000000..50e4680
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/PoseModifierImpl.java
@@ -0,0 +1,65 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier;
+
+import com.mojang.serialization.Codec;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.anim.Pose;
+import com.tiedup.remake.rig.anim.property.AnimationProperty.PoseModifier;
+import com.tiedup.remake.rig.anim.types.DynamicAnimation;
+import com.tiedup.remake.rig.patch.LivingEntityPatch;
+
+/**
+ * Phase 3 D1 — data-driven concrete implementation of the functional
+ * {@link PoseModifier} interface.
+ *
+ * <p>{@link PoseModifier} is a raw lambda {@code (self, pose, patch, elapsed,
+ * partialTick) -> void}, which is not serializable on its own. This interface
+ * extends it with a {@link #type()} identifier and a dispatch codec so that
+ * datapack authors can write concrete modifiers in JSON :
+ * <pre>{@code
+ *   "pose_modifier": { "type": "tiedup:joint_rotation_offset",
+ *                       "joint": "upper_arm_left",
+ *                       "pitch": 15.0, "yaw": 0.0, "roll": 0.0 }
+ * }</pre>
+ *
+ * <p>Unlike {@link com.tiedup.remake.rig.anim.action.AnimationAction} which
+ * supports lists (a single animation can fire many actions), a single
+ * {@code pose_modifier} slot accepts exactly one modifier — because
+ * {@code StaticAnimationProperty.POSE_MODIFIER} is declared as {@code <PoseModifier>}
+ * (singular) and the consumer
+ * ({@link com.tiedup.remake.rig.anim.types.StaticAnimation#modifyPose}) calls
+ * {@code poseModifier.modify(...)} exactly once. Authors who want composition
+ * should chain via {@link com.tiedup.remake.rig.anim.modifier.impl.ChainedPoseModifier}.
+ *
+ * <p>All implementations must be side-safe : {@link PoseModifier#modify} is
+ * invoked in both client render and server logic ticks. Implementations that
+ * mutate the pose must do so deterministically from the inputs only, no IO or
+ * world state.
+ */
+public interface PoseModifierImpl extends PoseModifier {
+
+	/**
+	 * Dispatch codec — reads the {@code "type"} field and delegates to the
+	 * codec registered for that {@link ResourceLocation}.
+	 */
+	Codec<PoseModifierImpl> CODEC = PoseModifierRegistry.dispatchCodec();
+
+	/**
+	 * The registered type id of this modifier (e.g.
+	 * {@code tiedup:joint_rotation_offset}).
+	 */
+	ResourceLocation type();
+
+	/**
+	 * Forwarded from {@link PoseModifier#modify}. Subinterface so that the
+	 * generic functional contract stays visible at the implementation site
+	 * without Java default-method ambiguity.
+	 */
+	@Override
+	void modify(DynamicAnimation self, Pose pose, LivingEntityPatch<?> entitypatch, float elapsedTime, float partialTick);
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/PoseModifierRegistry.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/PoseModifierRegistry.java
new file mode 100644
index 0000000..f75d8db
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/PoseModifierRegistry.java
@@ -0,0 +1,82 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.DataResult;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.anim.modifier.impl.ChainedPoseModifier;
+import com.tiedup.remake.rig.anim.modifier.impl.JointRotationOffsetModifier;
+import com.tiedup.remake.rig.anim.modifier.impl.JointTranslationOffsetModifier;
+
+/**
+ * Registry of {@link PoseModifierImpl} type ids → codecs. Mirrors the design
+ * of {@link com.tiedup.remake.rig.anim.action.AnimationActionRegistry}.
+ *
+ * <p>Three base impls are registered in the static initializer :
+ * <ul>
+ *   <li>{@code tiedup:joint_rotation_offset} — nudge a single joint's rotation</li>
+ *   <li>{@code tiedup:joint_translation_offset} — nudge a single joint's translation</li>
+ *   <li>{@code tiedup:chain} — run a list of modifiers in order</li>
+ * </ul>
+ *
+ * <p>Registering via the static init means a single reference to
+ * {@link PoseModifierImpl#CODEC} in a parse path is enough to bootstrap the
+ * dispatch table, same bootstrap contract as the action registry.
+ */
+public final class PoseModifierRegistry {
+
+	private static final Map<ResourceLocation, Codec<? extends PoseModifierImpl>> TYPES = new HashMap<>();
+
+	private PoseModifierRegistry() {}
+
+	/**
+	 * @throws IllegalStateException if {@code id} is already registered
+	 */
+	public static <T extends PoseModifierImpl> void register(ResourceLocation id, Codec<T> codec) {
+		if (TYPES.containsKey(id)) {
+			throw new IllegalStateException("Pose modifier type " + id + " is already registered.");
+		}
+
+		TYPES.put(id, codec);
+	}
+
+	/**
+	 * Unmodifiable view of all registered modifier types.
+	 */
+	public static Map<ResourceLocation, Codec<? extends PoseModifierImpl>> types() {
+		return Collections.unmodifiableMap(TYPES);
+	}
+
+	public static Codec<? extends PoseModifierImpl> getCodec(ResourceLocation id) {
+		return TYPES.get(id);
+	}
+
+	public static Codec<PoseModifierImpl> dispatchCodec() {
+		return ResourceLocation.CODEC.partialDispatch(
+			"type",
+			mod -> DataResult.success(mod.type()),
+			id -> {
+				Codec<? extends PoseModifierImpl> codec = TYPES.get(id);
+				if (codec == null) {
+					return DataResult.error(() -> "Unknown pose modifier type: " + id);
+				}
+				return DataResult.success(codec);
+			}
+		);
+	}
+
+	static {
+		register(JointRotationOffsetModifier.ID, JointRotationOffsetModifier.CODEC);
+		register(JointTranslationOffsetModifier.ID, JointTranslationOffsetModifier.CODEC);
+		register(ChainedPoseModifier.ID, ChainedPoseModifier.CODEC);
+	}
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/ChainedPoseModifier.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/ChainedPoseModifier.java
new file mode 100644
index 0000000..4faf4f7
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/ChainedPoseModifier.java
@@ -0,0 +1,97 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier.impl;
+
+import java.util.List;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.DataResult;
+import com.mojang.serialization.Decoder;
+import com.mojang.serialization.DynamicOps;
+import com.mojang.serialization.Encoder;
+import com.mojang.serialization.codecs.RecordCodecBuilder;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.TiedUpRigConstants;
+import com.tiedup.remake.rig.anim.Pose;
+import com.tiedup.remake.rig.anim.modifier.PoseModifierImpl;
+import com.tiedup.remake.rig.anim.types.DynamicAnimation;
+import com.tiedup.remake.rig.patch.LivingEntityPatch;
+
+/**
+ * Composite modifier — runs a list of modifiers sequentially on the same pose.
+ * Compensates for the singular {@code POSE_MODIFIER} property slot (only one
+ * modifier can be attached to an animation, but authors often need several
+ * per-joint nudges).
+ *
+ * <p>JSON schema :
+ * <pre>{@code
+ *   { "type": "tiedup:chain",
+ *     "modifiers": [
+ *       { "type": "tiedup:joint_rotation_offset",   "joint": "upper_arm_left",  "pitch": 15.0 },
+ *       { "type": "tiedup:joint_translation_offset","joint": "hand_right",      "y":   -0.05 }
+ *     ] }
+ * }</pre>
+ *
+ * <p>Nested chains are allowed (no cycle detection — an author-written cycle
+ * would manifest as a {@link StackOverflowError} at tick time, which is
+ * identifiable and not worth defensive code). Execution order is list order.
+ */
+public record ChainedPoseModifier(
+	List<PoseModifierImpl> modifiers
+) implements PoseModifierImpl {
+
+	public static final ResourceLocation ID = TiedUpRigConstants.identifier("chain");
+
+	/**
+	 * Hand-rolled lazy codec. We cannot use a {@link RecordCodecBuilder} that
+	 * references {@link PoseModifierImpl#CODEC} at static-init time because
+	 * that would create a cycle :
+	 * {@code ChainedPoseModifier.CODEC → PoseModifierImpl.CODEC
+	 *        → PoseModifierRegistry.<clinit> → ChainedPoseModifier.CODEC}
+	 * which leaves ChainedPoseModifier.CODEC null during the registry
+	 * registration call. Instead, we defer the recursive lookup by calling
+	 * {@link PoseModifierImpl#CODEC} inside the encode/decode bodies, which
+	 * run only at (de)serialization time — long after all static inits have
+	 * completed.
+	 */
+	public static final Codec<ChainedPoseModifier> CODEC = Codec.of(
+		new Encoder<ChainedPoseModifier>() {
+			@Override
+			public <T> DataResult<T> encode(ChainedPoseModifier input, DynamicOps<T> ops, T prefix) {
+				return PoseModifierImpl.CODEC.listOf()
+					.encodeStart(ops, input.modifiers())
+					.flatMap(list -> ops.mergeToMap(prefix, ops.createString("modifiers"), list));
+			}
+		},
+		new Decoder<ChainedPoseModifier>() {
+			@Override
+			public <T> DataResult<com.mojang.datafixers.util.Pair<ChainedPoseModifier, T>> decode(DynamicOps<T> ops, T input) {
+				return ops.getMap(input).flatMap(map -> {
+					T modifiersField = map.get("modifiers");
+					if (modifiersField == null) {
+						return DataResult.error(() -> "Missing field 'modifiers' in tiedup:chain");
+					}
+					return PoseModifierImpl.CODEC.listOf()
+						.parse(ops, modifiersField)
+						.map(list -> com.mojang.datafixers.util.Pair.of(new ChainedPoseModifier(list), input));
+				});
+			}
+		}
+	);
+
+	@Override
+	public ResourceLocation type() {
+		return ID;
+	}
+
+	@Override
+	public void modify(DynamicAnimation self, Pose pose, LivingEntityPatch<?> entitypatch, float elapsedTime, float partialTick) {
+		for (PoseModifierImpl m : this.modifiers) {
+			m.modify(self, pose, entitypatch, elapsedTime, partialTick);
+		}
+	}
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/ConstantFactorSpeedModifier.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/ConstantFactorSpeedModifier.java
new file mode 100644
index 0000000..794271e
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/ConstantFactorSpeedModifier.java
@@ -0,0 +1,47 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier.impl;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.codecs.RecordCodecBuilder;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.TiedUpRigConstants;
+import com.tiedup.remake.rig.anim.modifier.PlaybackSpeedModifierImpl;
+import com.tiedup.remake.rig.anim.types.DynamicAnimation;
+import com.tiedup.remake.rig.patch.LivingEntityPatch;
+
+/**
+ * Multiply the current playback speed by a fixed factor every tick.
+ *
+ * <p>JSON schema :
+ * <pre>{@code
+ *   "play_speed_modifier": { "type": "tiedup:constant_factor", "factor": 0.5 }
+ * }</pre>
+ *
+ * <p>A {@code factor} of {@code 1.0} is a no-op. Negative factors technically
+ * work (animation plays backward) but the reverse flag in
+ * {@link com.tiedup.remake.rig.anim.AnimationPlayer} already handles that
+ * cleanly — prefer that over a negative speed modifier.
+ */
+public record ConstantFactorSpeedModifier(float factor) implements PlaybackSpeedModifierImpl {
+
+	public static final ResourceLocation ID = TiedUpRigConstants.identifier("constant_factor");
+
+	public static final Codec<ConstantFactorSpeedModifier> CODEC = RecordCodecBuilder.create(i -> i.group(
+		Codec.FLOAT.fieldOf("factor").forGetter(ConstantFactorSpeedModifier::factor)
+	).apply(i, ConstantFactorSpeedModifier::new));
+
+	@Override
+	public ResourceLocation type() {
+		return ID;
+	}
+
+	@Override
+	public float modify(DynamicAnimation self, LivingEntityPatch<?> entitypatch, float speed, float prevElapsedTime, float elapsedTime) {
+		return speed * this.factor;
+	}
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/JointRotationOffsetModifier.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/JointRotationOffsetModifier.java
new file mode 100644
index 0000000..852d939
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/JointRotationOffsetModifier.java
@@ -0,0 +1,79 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier.impl;
+
+import org.joml.Quaternionf;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.codecs.RecordCodecBuilder;
+
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.util.Mth;
+
+import com.tiedup.remake.rig.TiedUpRigConstants;
+import com.tiedup.remake.rig.anim.Pose;
+import com.tiedup.remake.rig.anim.modifier.PoseModifierImpl;
+import com.tiedup.remake.rig.anim.types.DynamicAnimation;
+import com.tiedup.remake.rig.armature.JointTransform;
+import com.tiedup.remake.rig.patch.LivingEntityPatch;
+
+/**
+ * Rotate a single named joint by a fixed Euler offset (degrees) at every tick
+ * of the animation. Bondage pipeline use-case : lock a restrained arm joint to
+ * a tighter angle than the authored animation provides.
+ *
+ * <p>JSON schema :
+ * <pre>{@code
+ *   { "type": "tiedup:joint_rotation_offset",
+ *     "joint": "upper_arm_left",
+ *     "pitch": 15.0,
+ *     "yaw": 0.0,
+ *     "roll": 0.0 }
+ * }</pre>
+ *
+ * <p>Angles default to zero if omitted — a {@code joint_rotation_offset} with
+ * all three zero is a no-op (author error, logged nowhere — by design, since
+ * it's a cheap operation and a valid edge case during iteration).
+ *
+ * <p>If the joint is absent from the pose, this modifier is a silent no-op :
+ * the authored animation simply doesn't touch that joint on this frame. This
+ * matches the semantics of {@link Pose#orElseEmpty} used elsewhere.
+ */
+public record JointRotationOffsetModifier(
+	String joint,
+	float pitch,
+	float yaw,
+	float roll
+) implements PoseModifierImpl {
+
+	public static final ResourceLocation ID = TiedUpRigConstants.identifier("joint_rotation_offset");
+
+	public static final Codec<JointRotationOffsetModifier> CODEC = RecordCodecBuilder.create(i -> i.group(
+		Codec.STRING.fieldOf("joint").forGetter(JointRotationOffsetModifier::joint),
+		Codec.FLOAT.optionalFieldOf("pitch", 0.0F).forGetter(JointRotationOffsetModifier::pitch),
+		Codec.FLOAT.optionalFieldOf("yaw", 0.0F).forGetter(JointRotationOffsetModifier::yaw),
+		Codec.FLOAT.optionalFieldOf("roll", 0.0F).forGetter(JointRotationOffsetModifier::roll)
+	).apply(i, JointRotationOffsetModifier::new));
+
+	@Override
+	public ResourceLocation type() {
+		return ID;
+	}
+
+	@Override
+	public void modify(DynamicAnimation self, Pose pose, LivingEntityPatch<?> entitypatch, float elapsedTime, float partialTick) {
+		if (!pose.hasTransform(this.joint)) {
+			return;
+		}
+
+		JointTransform jt = pose.get(this.joint);
+		Quaternionf offset = new Quaternionf().rotationXYZ(
+			this.pitch * Mth.DEG_TO_RAD,
+			this.yaw * Mth.DEG_TO_RAD,
+			this.roll * Mth.DEG_TO_RAD
+		);
+		jt.rotation().mul(offset);
+	}
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/JointTranslationOffsetModifier.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/JointTranslationOffsetModifier.java
new file mode 100644
index 0000000..570f0fa
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/JointTranslationOffsetModifier.java
@@ -0,0 +1,64 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier.impl;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.codecs.RecordCodecBuilder;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.TiedUpRigConstants;
+import com.tiedup.remake.rig.anim.Pose;
+import com.tiedup.remake.rig.anim.modifier.PoseModifierImpl;
+import com.tiedup.remake.rig.anim.types.DynamicAnimation;
+import com.tiedup.remake.rig.armature.JointTransform;
+import com.tiedup.remake.rig.patch.LivingEntityPatch;
+
+/**
+ * Shift a single named joint by a fixed translation offset at every tick of
+ * the animation. Use-case : pull a constrained wrist joint closer to the
+ * furniture anchor than the authored animation puts it.
+ *
+ * <p>JSON schema :
+ * <pre>{@code
+ *   { "type": "tiedup:joint_translation_offset",
+ *     "joint": "hand_right",
+ *     "x": 0.0, "y": -0.05, "z": 0.02 }
+ * }</pre>
+ *
+ * <p>All three axes default to zero — a fully-zero offset is a no-op.
+ * Missing joint is a silent no-op (same contract as the rotation variant).
+ */
+public record JointTranslationOffsetModifier(
+	String joint,
+	float x,
+	float y,
+	float z
+) implements PoseModifierImpl {
+
+	public static final ResourceLocation ID = TiedUpRigConstants.identifier("joint_translation_offset");
+
+	public static final Codec<JointTranslationOffsetModifier> CODEC = RecordCodecBuilder.create(i -> i.group(
+		Codec.STRING.fieldOf("joint").forGetter(JointTranslationOffsetModifier::joint),
+		Codec.FLOAT.optionalFieldOf("x", 0.0F).forGetter(JointTranslationOffsetModifier::x),
+		Codec.FLOAT.optionalFieldOf("y", 0.0F).forGetter(JointTranslationOffsetModifier::y),
+		Codec.FLOAT.optionalFieldOf("z", 0.0F).forGetter(JointTranslationOffsetModifier::z)
+	).apply(i, JointTranslationOffsetModifier::new));
+
+	@Override
+	public ResourceLocation type() {
+		return ID;
+	}
+
+	@Override
+	public void modify(DynamicAnimation self, Pose pose, LivingEntityPatch<?> entitypatch, float elapsedTime, float partialTick) {
+		if (!pose.hasTransform(this.joint)) {
+			return;
+		}
+
+		JointTransform jt = pose.get(this.joint);
+		jt.translation().add(this.x, this.y, this.z);
+	}
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/LinearRampSpeedModifier.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/LinearRampSpeedModifier.java
new file mode 100644
index 0000000..65f7fea
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/LinearRampSpeedModifier.java
@@ -0,0 +1,72 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier.impl;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.codecs.RecordCodecBuilder;
+
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.util.Mth;
+
+import com.tiedup.remake.rig.TiedUpRigConstants;
+import com.tiedup.remake.rig.anim.modifier.PlaybackSpeedModifierImpl;
+import com.tiedup.remake.rig.anim.types.DynamicAnimation;
+import com.tiedup.remake.rig.patch.LivingEntityPatch;
+
+/**
+ * Ramp the playback speed factor linearly from {@code from} to {@code to} over
+ * the time window {@code [startTime, endTime]} (in seconds of animation
+ * elapsed). Outside the window, clamps to the boundary value.
+ *
+ * <p>JSON schema :
+ * <pre>{@code
+ *   "play_speed_modifier": { "type": "tiedup:linear_ramp",
+ *                             "from": 0.2, "to": 1.0,
+ *                             "start_time": 0.0, "end_time": 0.5 }
+ * }</pre>
+ *
+ * <p>Use-case : hesitant-start animations (slow initial frames, then ramp to
+ * full speed for the payoff). The modifier's output is multiplied against the
+ * base speed by {@link com.tiedup.remake.rig.anim.AnimationPlayer#tick}, so
+ * {@code from=1.0, to=1.0} is a no-op.
+ *
+ * <p>{@code end_time <= start_time} degenerates to returning {@code to} for
+ * all {@code elapsedTime >= start_time} (clamped path above saturation).
+ */
+public record LinearRampSpeedModifier(
+	float from,
+	float to,
+	float startTime,
+	float endTime
+) implements PlaybackSpeedModifierImpl {
+
+	public static final ResourceLocation ID = TiedUpRigConstants.identifier("linear_ramp");
+
+	public static final Codec<LinearRampSpeedModifier> CODEC = RecordCodecBuilder.create(i -> i.group(
+		Codec.FLOAT.fieldOf("from").forGetter(LinearRampSpeedModifier::from),
+		Codec.FLOAT.fieldOf("to").forGetter(LinearRampSpeedModifier::to),
+		Codec.FLOAT.optionalFieldOf("start_time", 0.0F).forGetter(LinearRampSpeedModifier::startTime),
+		Codec.FLOAT.optionalFieldOf("end_time", 1.0F).forGetter(LinearRampSpeedModifier::endTime)
+	).apply(i, LinearRampSpeedModifier::new));
+
+	@Override
+	public ResourceLocation type() {
+		return ID;
+	}
+
+	@Override
+	public float modify(DynamicAnimation self, LivingEntityPatch<?> entitypatch, float speed, float prevElapsedTime, float elapsedTime) {
+		float factor;
+		if (elapsedTime <= this.startTime) {
+			factor = this.from;
+		} else if (elapsedTime >= this.endTime || this.endTime <= this.startTime) {
+			factor = this.to;
+		} else {
+			float progress = (elapsedTime - this.startTime) / (this.endTime - this.startTime);
+			factor = Mth.lerp(progress, this.from, this.to);
+		}
+		return speed * factor;
+	}
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/LoopSectionTimeModifier.java b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/LoopSectionTimeModifier.java
new file mode 100644
index 0000000..bd87618
--- /dev/null
+++ b/src/main/java/com/tiedup/remake/rig/anim/modifier/impl/LoopSectionTimeModifier.java
@@ -0,0 +1,68 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier.impl;
+
+import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.codecs.RecordCodecBuilder;
+
+import net.minecraft.resources.ResourceLocation;
+
+import com.tiedup.remake.rig.TiedUpRigConstants;
+import com.tiedup.remake.rig.anim.modifier.PlaybackTimeModifierImpl;
+import com.tiedup.remake.rig.anim.types.DynamicAnimation;
+import com.tiedup.remake.rig.patch.LivingEntityPatch;
+
+/**
+ * Rewind the animation playhead back to {@code loopStart} every time it
+ * crosses {@code loopEnd}. Matches the «sustain loop» pattern used e.g. for
+ * breathing idles inside a rest phase — the intro plays once, a middle section
+ * loops, and the outro is triggered by a separate state transition (not this
+ * modifier).
+ *
+ * <p>JSON schema :
+ * <pre>{@code
+ *   "elapsed_time_modifier": { "type": "tiedup:loop_section",
+ *                               "loop_start": 0.3, "loop_end": 0.8 }
+ * }</pre>
+ *
+ * <p>This modifier is a pure function of {@code elapsedTime} — it does not
+ * mutate the animation. The {@code prevElapsedTime} is rewound symmetrically
+ * so event triggers using {@code [prev, elapsed]} windows still fire cleanly
+ * after the rewind.
+ *
+ * <p>Invariant : {@code loopStart < loopEnd}. Violating this yields undefined
+ * behaviour (probably a NaN or an instant loop) — no defensive check because
+ * the author would notice immediately on first playback.
+ */
+public record LoopSectionTimeModifier(
+	float loopStart,
+	float loopEnd
+) implements PlaybackTimeModifierImpl {
+
+	public static final ResourceLocation ID = TiedUpRigConstants.identifier("loop_section");
+
+	public static final Codec<LoopSectionTimeModifier> CODEC = RecordCodecBuilder.create(i -> i.group(
+		Codec.FLOAT.fieldOf("loop_start").forGetter(LoopSectionTimeModifier::loopStart),
+		Codec.FLOAT.fieldOf("loop_end").forGetter(LoopSectionTimeModifier::loopEnd)
+	).apply(i, LoopSectionTimeModifier::new));
+
+	@Override
+	public ResourceLocation type() {
+		return ID;
+	}
+
+	@Override
+	public Pair<Float, Float> modify(DynamicAnimation self, LivingEntityPatch<?> entitypatch, float speed, float prevElapsedTime, float elapsedTime) {
+		if (elapsedTime >= this.loopEnd) {
+			float overshoot = elapsedTime - this.loopEnd;
+			float sectionLen = this.loopEnd - this.loopStart;
+			float wrapped = this.loopStart + (overshoot % sectionLen);
+			float prevWrapped = prevElapsedTime - (elapsedTime - wrapped);
+			return Pair.of(prevWrapped, wrapped);
+		}
+		return Pair.of(prevElapsedTime, elapsedTime);
+	}
+}
diff --git a/src/main/java/com/tiedup/remake/rig/anim/property/AnimationProperty.java b/src/main/java/com/tiedup/remake/rig/anim/property/AnimationProperty.java
index b5c439e..4016497 100644
--- a/src/main/java/com/tiedup/remake/rig/anim/property/AnimationProperty.java
+++ b/src/main/java/com/tiedup/remake/rig/anim/property/AnimationProperty.java
@@ -17,6 +17,7 @@ import com.google.common.collect.Maps;
 import com.google.gson.JsonElement;
 import com.mojang.datafixers.util.Pair;
 import com.mojang.serialization.Codec;
+import com.mojang.serialization.DataResult;
 import com.mojang.serialization.JsonOps;
 
 import net.minecraft.resources.ResourceLocation;
@@ -29,6 +30,9 @@ import com.tiedup.remake.rig.anim.LivingMotion;
 import com.tiedup.remake.rig.anim.Pose;
 import com.tiedup.remake.rig.anim.TransformSheet;
 import com.tiedup.remake.rig.anim.action.DataDrivenAnimationEvents;
+import com.tiedup.remake.rig.anim.modifier.PlaybackSpeedModifierImpl;
+import com.tiedup.remake.rig.anim.modifier.PlaybackTimeModifierImpl;
+import com.tiedup.remake.rig.anim.modifier.PoseModifierImpl;
 import com.tiedup.remake.rig.anim.property.AnimationEvent.SimpleEvent;
 import com.tiedup.remake.rig.anim.property.MoveCoordFunctions.MoveCoordGetter;
 import com.tiedup.remake.rig.anim.property.MoveCoordFunctions.MoveCoordSetter;
@@ -46,6 +50,53 @@ import com.tiedup.remake.rig.patch.item.CapabilityItem;
 
 public abstract class AnimationProperty<T> {
 	private static final Map<String, AnimationProperty<?>> SERIALIZABLE_ANIMATION_PROPERTY_KEYS = Maps.newHashMap();
+
+	/**
+	 * Phase 3 D1 — {@link LivingMotion} codec. {@code LivingMotion} is an
+	 * {@link com.tiedup.remake.rig.util.ExtendableEnum} so its string form is
+	 * the {@link #toString()} lowercased ; we deserialize via
+	 * {@code ENUM_MANAGER.getOrThrow(String)} which throws if unknown.
+	 */
+	public static final Codec<LivingMotion> LIVING_MOTION_CODEC = Codec.STRING.flatXmap(
+		name -> {
+			try {
+				return DataResult.success(LivingMotion.ENUM_MANAGER.getOrThrow(name));
+			} catch (java.util.NoSuchElementException e) {
+				return DataResult.error(() -> "Unknown living motion: " + name);
+			}
+		},
+		motion -> DataResult.success(motion.toString().toLowerCase())
+	);
+
+	/**
+	 * Phase 3 D1 — {@link TimePairList} codec. Authored as a flat list of
+	 * floats that must have an even length (pairs of {@code begin, end}).
+	 * Odd-length lists surface as a codec error (logged + property skipped).
+	 *
+	 * <p>JSON shape : {@code [0.0, 0.3, 0.6, 0.9]} → two pairs, {@code [0,0.3]}
+	 * and {@code [0.6,0.9]}. We go through a float[] because {@code
+	 * TimePairList.create} is varargs. Decoding via
+	 * {@link TimePairList#create(float...)} surfaces the odd-count invariant
+	 * via {@link IllegalArgumentException} — wrapped into a {@link DataResult}
+	 * error.
+	 */
+	public static final Codec<TimePairList> TIME_PAIR_LIST_CODEC = Codec.FLOAT.listOf().flatXmap(
+		list -> {
+			if ((list.size() & 1) != 0) {
+				return DataResult.error(() -> "TimePairList must have an even number of floats, got " + list.size());
+			}
+			float[] arr = new float[list.size()];
+			for (int i = 0; i < arr.length; i++) {
+				arr[i] = list.get(i);
+			}
+			return DataResult.success(TimePairList.create(arr));
+		},
+		// Encode back : no public accessor on TimePairList's internal pairs,
+		// and the property pipeline is read-only from JSON (never re-serialized
+		// to disk) — we therefore refuse encoding. If round-trip becomes a
+		// requirement, expose TimePairList#asFloatArray() first.
+		tpl -> DataResult.error(() -> "TimePairList encoding is not supported (read-only datapack property)")
+	);
 	
 	@SuppressWarnings("unchecked")
 	public static <T> AnimationProperty<T> getSerializableProperty(String name) {
@@ -135,38 +186,116 @@ public abstract class AnimationProperty<T> {
 		
 		/**
 		 * An event triggered when entity changes an item in hand.
-		 * Retenu comme hook datapack : un event écrit en JSON par un datapack tiers peut s'abonner
-		 * au changement d'item porté pour déclencher une réaction (voir Phase 3 data-driven anims).
+		 *
+		 * <p>Phase 3 D1 — Category C, SKIPPED. The item-change event is a
+		 * combat/equipment hook from Epic Fight upstream ; no bondage pipeline
+		 * consumer reads this property today. Re-enable (register a codec) when
+		 * weapon/equipment reactive animations are reintroduced.
 		 */
 		public static final StaticAnimationProperty<SimpleEvent<AnimationEvent.E2<CapabilityItem, CapabilityItem>>> ON_ITEM_CHANGE_EVENT = new StaticAnimationProperty<SimpleEvent<AnimationEvent.E2<CapabilityItem, CapabilityItem>>> ();
-		
+
 		/**
 		 * You can modify the playback speed of the animation.
+		 *
+		 * <p>Phase 3 D1 — serializable via the
+		 * {@link PlaybackSpeedModifierImpl#CODEC} dispatch codec (Category B).
+		 * JSON example :
+		 * <pre>{@code
+		 *   "play_speed_modifier": { "type": "tiedup:constant_factor", "factor": 0.5 }
+		 * }</pre>
+		 * The upcast {@code PlaybackSpeedModifierImpl → PlaybackSpeedModifier}
+		 * is implicit (sub-interface) so the property stays typed as the wider
+		 * functional type for backward-compat with existing consumers in
+		 * {@link com.tiedup.remake.rig.anim.AnimationPlayer#tick} and
+		 * {@link com.tiedup.remake.rig.anim.client.AnimationSubFileReader}.
 		 */
-		public static final StaticAnimationProperty<PlaybackSpeedModifier> PLAY_SPEED_MODIFIER = new StaticAnimationProperty<PlaybackSpeedModifier> ();
+		public static final StaticAnimationProperty<PlaybackSpeedModifier> PLAY_SPEED_MODIFIER = new StaticAnimationProperty<PlaybackSpeedModifier> (
+			"play_speed_modifier",
+			PlaybackSpeedModifierImpl.CODEC.xmap(
+				impl -> (PlaybackSpeedModifier) impl,
+				base -> {
+					if (base instanceof PlaybackSpeedModifierImpl impl) return impl;
+					throw new IllegalStateException("PlaybackSpeedModifier value is not a serializable impl: " + base);
+				}
+			)
+		);
+
+		/**
+		 * You can modify the elapsed playback time of the animation.
+		 *
+		 * <p>Phase 3 D1 — serializable via the
+		 * {@link PlaybackTimeModifierImpl#CODEC} dispatch codec (Category B).
+		 * JSON example :
+		 * <pre>{@code
+		 *   "elapsed_time_modifier": { "type": "tiedup:loop_section",
+		 *                               "loop_start": 0.3, "loop_end": 0.8 }
+		 * }</pre>
+		 */
+		public static final StaticAnimationProperty<PlaybackTimeModifier> ELAPSED_TIME_MODIFIER = new StaticAnimationProperty<PlaybackTimeModifier> (
+			"elapsed_time_modifier",
+			PlaybackTimeModifierImpl.CODEC.xmap(
+				impl -> (PlaybackTimeModifier) impl,
+				base -> {
+					if (base instanceof PlaybackTimeModifierImpl impl) return impl;
+					throw new IllegalStateException("PlaybackTimeModifier value is not a serializable impl: " + base);
+				}
+			)
+		);
+
+		/**
+		 * This property will be called both in client and server when modifying the pose.
+		 *
+		 * <p>Phase 3 D1 — serializable via the
+		 * {@link PoseModifierImpl#CODEC} dispatch codec (Category B). Key
+		 * artist unlock for bondage : per-joint nudges can be authored
+		 * from JSON :
+		 * <pre>{@code
+		 *   "pose_modifier": { "type": "tiedup:chain",
+		 *                       "modifiers": [
+		 *                         { "type": "tiedup:joint_rotation_offset",    "joint": "upper_arm_left",  "pitch": 15.0 },
+		 *                         { "type": "tiedup:joint_translation_offset", "joint": "hand_right",      "y":    -0.05 }
+		 *                       ] }
+		 * }</pre>
+		 */
+		public static final StaticAnimationProperty<PoseModifier> POSE_MODIFIER = new StaticAnimationProperty<PoseModifier> (
+			"pose_modifier",
+			PoseModifierImpl.CODEC.xmap(
+				impl -> (PoseModifier) impl,
+				base -> {
+					if (base instanceof PoseModifierImpl impl) return impl;
+					throw new IllegalStateException("PoseModifier value is not a serializable impl: " + base);
+				}
+			)
+		);
+
+		/**
+		 * Fix the head rotation to the player's body rotation.
+		 *
+		 * <p>Phase 3 D1 — Category A, trivial boolean codec.
+		 */
+		public static final StaticAnimationProperty<Boolean> FIXED_HEAD_ROTATION = new StaticAnimationProperty<Boolean> (
+			"fixed_head_rotation",
+			Codec.BOOL
+		);
 		
 		/**
-		 * You can modify the playback speed of the animation.
-		 */
-		public static final StaticAnimationProperty<PlaybackTimeModifier> ELAPSED_TIME_MODIFIER = new StaticAnimationProperty<PlaybackTimeModifier> ();
-		
-		/**
-		 * This property will be called both in client and server when modifying the pose
-		 */
-		public static final StaticAnimationProperty<PoseModifier> POSE_MODIFIER = new StaticAnimationProperty<PoseModifier> ();
-		
-		/**
-		 * Fix the head rotation to the player's body rotation
-		 */
-		public static final StaticAnimationProperty<Boolean> FIXED_HEAD_ROTATION = new StaticAnimationProperty<Boolean> ();
-		
-		/**
-		 * Defines static animations as link animation when the animation is followed by a specific animation
+		 * Defines static animations as link animation when the animation is followed by a specific animation.
+		 *
+		 * <p>Phase 3 D1 — Category D, SKIPPED. The map value is an
+		 * {@link AnimationAccessor} which is an internal registry handle (not a
+		 * data-describable object) ; resolving accessors from ids requires the
+		 * {@link com.tiedup.remake.rig.anim.AnimationManager} to already be
+		 * populated, which is only true after full resource-pack load. The
+		 * existing sub-file reader path handles transitions correctly — moving
+		 * the parse here would create a chicken-and-egg bootstrapping issue.
 		 */
 		public static final StaticAnimationProperty<Map<ResourceLocation, AnimationAccessor<? extends StaticAnimation>>> TRANSITION_ANIMATIONS_FROM = new StaticAnimationProperty<Map<ResourceLocation, AnimationAccessor<? extends StaticAnimation>>> ();
-		
+
 		/**
-		 * Defines static animations as link animation when the animation is following a specific animation
+		 * Defines static animations as link animation when the animation is following a specific animation.
+		 *
+		 * <p>Phase 3 D1 — Category D, SKIPPED (same reason as
+		 * {@link #TRANSITION_ANIMATIONS_FROM}).
 		 */
 		public static final StaticAnimationProperty<Map<ResourceLocation, AnimationAccessor<? extends StaticAnimation>>> TRANSITION_ANIMATIONS_TO = new StaticAnimationProperty<Map<ResourceLocation, AnimationAccessor<? extends StaticAnimation>>> ();
 		
@@ -176,19 +305,38 @@ public abstract class AnimationProperty<T> {
 		public static final StaticAnimationProperty<Boolean> NO_PHYSICS = new StaticAnimationProperty<Boolean> ("no_physics", Codec.BOOL);
 		
 		/**
-		 * Inverse kinematics information
+		 * Inverse kinematics information.
+		 *
+		 * <p>Phase 3 D1 — Category D, SKIPPED. {@link InverseKinematicsDefinition}
+		 * holds complex baked state (joint chains, pole targets, constraint
+		 * weights) that is authored via a dedicated IK definition file, not
+		 * via the animation properties block. See the sub-file reader in
+		 * {@link com.tiedup.remake.rig.anim.client.AnimationSubFileReader}.
 		 */
 		public static final StaticAnimationProperty<List<InverseKinematicsDefinition>> IK_DEFINITION = new StaticAnimationProperty<List<InverseKinematicsDefinition>> ();
-		
+
 		/**
-		 * This property automatically baked when animation is loaded
+		 * This property automatically baked when animation is loaded.
+		 *
+		 * <p>Phase 3 D1 — Category D, SKIPPED. Never authored in JSON : this
+		 * slot is populated at load time by
+		 * {@link com.tiedup.remake.rig.anim.types.StaticAnimation#loadAnimation}
+		 * from {@link #IK_DEFINITION} which is then cleared.
 		 */
 		public static final StaticAnimationProperty<List<BakedInverseKinematicsDefinition>> BAKED_IK_DEFINITION = new StaticAnimationProperty<List<BakedInverseKinematicsDefinition>> ();
-		
+
 		/**
-		 * This property reset the entity's living motion
+		 * This property reset the entity's living motion.
+		 *
+		 * <p>Phase 3 D1 — Category A, codec uses the shared
+		 * {@link AnimationProperty#LIVING_MOTION_CODEC} which resolves against
+		 * {@link LivingMotion#ENUM_MANAGER}. JSON example :
+		 * <pre>{@code "reset_living_motion": "idle"}</pre>
 		 */
-		public static final StaticAnimationProperty<LivingMotion> RESET_LIVING_MOTION = new StaticAnimationProperty<LivingMotion> ();
+		public static final StaticAnimationProperty<LivingMotion> RESET_LIVING_MOTION = new StaticAnimationProperty<LivingMotion> (
+			"reset_living_motion",
+			LIVING_MOTION_CODEC
+		);
 	}
 	
 	public static class ActionAnimationProperty<T> extends StaticAnimationProperty<T> {
@@ -218,11 +366,25 @@ public abstract class AnimationProperty<T> {
 		
 		/**
 		 * This property determines the time of entity not affected by gravity.
+		 *
+		 * <p>Phase 3 D1 — Category A, codec uses the shared
+		 * {@link AnimationProperty#TIME_PAIR_LIST_CODEC}. JSON example :
+		 * <pre>{@code "no_gravity_time": [0.1, 0.4, 0.6, 0.9]}</pre>
+		 * (two no-gravity windows : [0.1..0.4] and [0.6..0.9]).
 		 */
-		public static final ActionAnimationProperty<TimePairList> NO_GRAVITY_TIME = new ActionAnimationProperty<TimePairList> ();
-		
+		public static final ActionAnimationProperty<TimePairList> NO_GRAVITY_TIME = new ActionAnimationProperty<TimePairList> (
+			"no_gravity_time",
+			TIME_PAIR_LIST_CODEC
+		);
+
 		/**
-		 * Coord of action animation
+		 * Coord of action animation.
+		 *
+		 * <p>Phase 3 D1 — Category C, SKIPPED. {@link TransformSheet} is
+		 * populated from the animation's baked keyframes by
+		 * {@link com.tiedup.remake.rig.asset.JsonAssetLoader} at load time
+		 * (not authored in the properties block). Exposing a codec here would
+		 * double-write an already-computed value.
 		 */
 		public static final ActionAnimationProperty<TransformSheet> COORD = new ActionAnimationProperty<TransformSheet> ();
 		
@@ -233,21 +395,38 @@ public abstract class AnimationProperty<T> {
 		
 		/**
 		 * You can specify the coord movement time in action animation. Must be registered in order of time.
+		 *
+		 * <p>Phase 3 D1 — Category A, codec uses
+		 * {@link AnimationProperty#TIME_PAIR_LIST_CODEC}.
 		 */
-		public static final ActionAnimationProperty<TimePairList> MOVE_TIME = new ActionAnimationProperty<TimePairList> ();
-		
+		public static final ActionAnimationProperty<TimePairList> MOVE_TIME = new ActionAnimationProperty<TimePairList> (
+			"move_time",
+			TIME_PAIR_LIST_CODEC
+		);
+
 		/**
 		 * Set the dynamic coordinates of {@link ActionAnimation}. Called before creation of {@link LinkAnimation}.
+		 *
+		 * <p>Phase 3 D1 — Category C, SKIPPED. {@link MoveCoordSetter} is a
+		 * combat/action-movement hook from Epic Fight upstream ; the bondage
+		 * pipeline never authors these at the datapack level (coord work is
+		 * done via coord joints and the sub-file reader).
 		 */
 		public static final ActionAnimationProperty<MoveCoordSetter> COORD_SET_BEGIN = new ActionAnimationProperty<MoveCoordSetter> ();
-		
+
 		/**
 		 * Set the dynamic coordinates of {@link ActionAnimation}.
+		 *
+		 * <p>Phase 3 D1 — Category C, SKIPPED (same reason as
+		 * {@link #COORD_SET_BEGIN}).
 		 */
 		public static final ActionAnimationProperty<MoveCoordSetter> COORD_SET_TICK = new ActionAnimationProperty<MoveCoordSetter> ();
-		
+
 		/**
 		 * Set the coordinates of action animation.
+		 *
+		 * <p>Phase 3 D1 — Category C, SKIPPED (same reason as
+		 * {@link #COORD_SET_BEGIN}).
 		 */
 		public static final ActionAnimationProperty<MoveCoordGetter> COORD_GET = new ActionAnimationProperty<MoveCoordGetter> ();
 		
@@ -268,8 +447,17 @@ public abstract class AnimationProperty<T> {
 		
 		/**
 		 * This property determines the update time of {@link ActionAnimationProperty#COORD_SET_TICK}. If the current time out of the bound it uses {@link MoveCoordFunctions#RAW_COORD and MoveCoordFunctions#DIFF_FROM_PREV_COORD}}
+		 *
+		 * <p>Phase 3 D1 — Category A, codec uses
+		 * {@link AnimationProperty#TIME_PAIR_LIST_CODEC}. Still serialized
+		 * despite being tied to {@link #COORD_SET_TICK} (Category C) because
+		 * the underlying datatype is data and authoring the time windows
+		 * without the setter is still legal (it degrades to a no-op, cheap).
 		 */
-		public static final ActionAnimationProperty<TimePairList> COORD_UPDATE_TIME = new ActionAnimationProperty<TimePairList> ();
+		public static final ActionAnimationProperty<TimePairList> COORD_UPDATE_TIME = new ActionAnimationProperty<TimePairList> (
+			"coord_update_time",
+			TIME_PAIR_LIST_CODEC
+		);
 		
 		/**
 		 * This property determines if it reset the player basic attack combo counter or not.
@@ -278,29 +466,48 @@ public abstract class AnimationProperty<T> {
 		public static final ActionAnimationProperty<Boolean> RESET_PLAYER_COMBO_COUNTER = new ActionAnimationProperty<Boolean> ("reset_combo_attack_counter", Codec.BOOL);
 
 		/**
-		 * Provide destination of action animation {@link MoveCoordFunctions}
+		 * Provide destination of action animation {@link MoveCoordFunctions}.
+		 *
+		 * <p>Phase 3 D1 — Category C, SKIPPED. Combat-movement hook ; the
+		 * bondage pipeline would need a whole new destination-provider
+		 * registry to expose this via JSON, and there is no artist use-case
+		 * today.
 		 */
 		public static final ActionAnimationProperty<DestLocationProvider> DEST_LOCATION_PROVIDER = new ActionAnimationProperty<DestLocationProvider> ();
-		
+
 		/**
-		 * Provide y rotation of entity {@link MoveCoordFunctions}
+		 * Provide y rotation of entity {@link MoveCoordFunctions}.
+		 *
+		 * <p>Phase 3 D1 — Category C, SKIPPED (combat-rotation hook).
 		 */
 		public static final ActionAnimationProperty<YRotProvider> ENTITY_YROT_PROVIDER = new ActionAnimationProperty<YRotProvider> ();
-		
+
 		/**
-		 * Provide y rotation of tracing coord {@link MoveCoordFunctions}
+		 * Provide y rotation of tracing coord {@link MoveCoordFunctions}.
+		 *
+		 * <p>Phase 3 D1 — Category C, SKIPPED (combat-rotation hook).
 		 */
 		public static final ActionAnimationProperty<YRotProvider> DEST_COORD_YROT_PROVIDER = new ActionAnimationProperty<YRotProvider> ();
-		
+
 		/**
-		 * Decides the index of start key frame for coord transform, See also with {@link MoveCoordFunctions#TRACE_ORIGIN_AS_DESTINATION}
+		 * Decides the index of start key frame for coord transform, See also with {@link MoveCoordFunctions#TRACE_ORIGIN_AS_DESTINATION}.
+		 *
+		 * <p>Phase 3 D1 — Category A, trivial int codec.
 		 */
-		public static final ActionAnimationProperty<Integer> COORD_START_KEYFRAME_INDEX = new ActionAnimationProperty<Integer> ();
-		
+		public static final ActionAnimationProperty<Integer> COORD_START_KEYFRAME_INDEX = new ActionAnimationProperty<Integer> (
+			"coord_start_keyframe_index",
+			Codec.INT
+		);
+
 		/**
-		 * Decides the index of destination key frame for coord transform, See also with {@link MoveCoordFunctions#TRACE_ORIGIN_AS_DESTINATION}
+		 * Decides the index of destination key frame for coord transform, See also with {@link MoveCoordFunctions#TRACE_ORIGIN_AS_DESTINATION}.
+		 *
+		 * <p>Phase 3 D1 — Category A, trivial int codec.
 		 */
-		public static final ActionAnimationProperty<Integer> COORD_DEST_KEYFRAME_INDEX = new ActionAnimationProperty<Integer> ();
+		public static final ActionAnimationProperty<Integer> COORD_DEST_KEYFRAME_INDEX = new ActionAnimationProperty<Integer> (
+			"coord_dest_keyframe_index",
+			Codec.INT
+		);
 		
 		/**
 		 * Determines if an entity should look where a camera is looking at the beginning of an animation (player only)
@@ -343,15 +550,30 @@ public abstract class AnimationProperty<T> {
 		public static final AttackAnimationProperty<Float> REACH = new AttackAnimationProperty<Float> ("reach", Codec.FLOAT);
 	}
 	
+	/**
+	 * Combat-phase properties for attack animations.
+	 *
+	 * <p>Phase 3 D1 — entire class body is Category C (combat-only, EF
+	 * legacy). The constructor no longer registers properties in the shared
+	 * dispatch map (see the commented {@code super(...)} call below) — this
+	 * was deliberately neutered in a prior audit because the bondage pipeline
+	 * never reads {@link AttackPhaseProperty} values. The four
+	 * {@link ValueModifier} constants kept their names purely for static
+	 * reference by surviving combat-adjacent code paths ; the sound/tag/
+	 * location properties are forever null-codec. Do not add codecs here
+	 * until a combat feature is reintroduced (see V3-REW-11+ in the
+	 * roadmap) — instead, resurrect the commented {@code super} call first
+	 * so the dispatch map picks them up consistently.
+	 */
 	public static class AttackPhaseProperty<T> {
 		public AttackPhaseProperty(String rl, @Nullable Codec<? extends T> codecs) {
 			//super(rl, codecs);
 		}
-		
+
 		public AttackPhaseProperty() {
 			//this(null, null);
 		}
-		
+
 		public static final AttackPhaseProperty<ValueModifier> MAX_STRIKES_MODIFIER = new AttackPhaseProperty<ValueModifier> ("max_strikes", ValueModifier.CODEC);
 		public static final AttackPhaseProperty<ValueModifier> DAMAGE_MODIFIER = new AttackPhaseProperty<ValueModifier> ("damage", ValueModifier.CODEC);
 		public static final AttackPhaseProperty<ValueModifier> ARMOR_NEGATION_MODIFIER = new AttackPhaseProperty<ValueModifier> ("armor_negation", ValueModifier.CODEC);
diff --git a/src/test/java/com/tiedup/remake/rig/anim/modifier/PlaybackSpeedModifierRegistryTest.java b/src/test/java/com/tiedup/remake/rig/anim/modifier/PlaybackSpeedModifierRegistryTest.java
new file mode 100644
index 0000000..7c2d026
--- /dev/null
+++ b/src/test/java/com/tiedup/remake/rig/anim/modifier/PlaybackSpeedModifierRegistryTest.java
@@ -0,0 +1,109 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonPrimitive;
+import com.mojang.serialization.DataResult;
+import com.mojang.serialization.JsonOps;
+
+import net.minecraft.resources.ResourceLocation;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import com.tiedup.remake.rig.anim.modifier.impl.ConstantFactorSpeedModifier;
+import com.tiedup.remake.rig.anim.modifier.impl.LinearRampSpeedModifier;
+
+class PlaybackSpeedModifierRegistryTest {
+
+	@BeforeAll
+	static void forceClinit() {
+		assertNotNull(ConstantFactorSpeedModifier.ID);
+		assertNotNull(LinearRampSpeedModifier.ID);
+		assertNotNull(PlaybackSpeedModifierImpl.CODEC);
+	}
+
+	@Test
+	void baseImpls_registered() {
+		assertNotNull(PlaybackSpeedModifierRegistry.getCodec(ConstantFactorSpeedModifier.ID));
+		assertNotNull(PlaybackSpeedModifierRegistry.getCodec(LinearRampSpeedModifier.ID));
+	}
+
+	@Test
+	void getCodec_unknownType_returnsNull() {
+		assertNull(PlaybackSpeedModifierRegistry.getCodec(new ResourceLocation("foo", "bar")));
+	}
+
+	@Test
+	void register_duplicateId_throws() {
+		assertThrows(IllegalStateException.class, () ->
+			PlaybackSpeedModifierRegistry.register(ConstantFactorSpeedModifier.ID, ConstantFactorSpeedModifier.CODEC)
+		);
+	}
+
+	@Test
+	void constantFactor_roundtrip() {
+		ConstantFactorSpeedModifier original = new ConstantFactorSpeedModifier(0.5F);
+
+		DataResult<JsonElement> encoded = PlaybackSpeedModifierImpl.CODEC.encodeStart(JsonOps.INSTANCE, original);
+		assertTrue(encoded.result().isPresent(), "encode error : " + encoded.error());
+		JsonObject json = encoded.result().get().getAsJsonObject();
+		assertEquals("tiedup:constant_factor", json.get("type").getAsString());
+
+		DataResult<PlaybackSpeedModifierImpl> decoded = PlaybackSpeedModifierImpl.CODEC.parse(JsonOps.INSTANCE, json);
+		assertTrue(decoded.result().isPresent());
+		assertEquals(original, decoded.result().get());
+	}
+
+	@Test
+	void constantFactor_halvesSpeed() {
+		ConstantFactorSpeedModifier mod = new ConstantFactorSpeedModifier(0.5F);
+		assertEquals(1.0F, mod.modify(null, null, 2.0F, 0F, 0F), 1e-5F);
+	}
+
+	@Test
+	void linearRamp_roundtrip() {
+		LinearRampSpeedModifier original = new LinearRampSpeedModifier(0.2F, 1.0F, 0.0F, 0.5F);
+
+		DataResult<JsonElement> encoded = PlaybackSpeedModifierImpl.CODEC.encodeStart(JsonOps.INSTANCE, original);
+		assertTrue(encoded.result().isPresent());
+		JsonObject json = encoded.result().get().getAsJsonObject();
+
+		DataResult<PlaybackSpeedModifierImpl> decoded = PlaybackSpeedModifierImpl.CODEC.parse(JsonOps.INSTANCE, json);
+		assertTrue(decoded.result().isPresent());
+		assertEquals(original, decoded.result().get());
+	}
+
+	@Test
+	void linearRamp_interpolatesCorrectly() {
+		LinearRampSpeedModifier mod = new LinearRampSpeedModifier(0.0F, 1.0F, 0.0F, 1.0F);
+		// At elapsedTime=0.0, factor should be 0.0 → speed stays * 0 = 0
+		assertEquals(0.0F, mod.modify(null, null, 10F, 0F, 0.0F), 1e-5F);
+		// At elapsedTime=0.5, factor should be 0.5 → speed * 0.5
+		assertEquals(5.0F, mod.modify(null, null, 10F, 0F, 0.5F), 1e-4F);
+		// At elapsedTime=1.0, factor should be 1.0 → speed * 1.0
+		assertEquals(10.0F, mod.modify(null, null, 10F, 0F, 1.0F), 1e-5F);
+		// Beyond end_time → clamp to `to`.
+		assertEquals(10.0F, mod.modify(null, null, 10F, 0F, 2.0F), 1e-5F);
+	}
+
+	@Test
+	void dispatchCodec_unknownType_returnsError() {
+		JsonObject json = new JsonObject();
+		json.add("type", new JsonPrimitive("foo:unknown"));
+
+		DataResult<PlaybackSpeedModifierImpl> decoded = PlaybackSpeedModifierImpl.CODEC.parse(JsonOps.INSTANCE, json);
+		assertFalse(decoded.result().isPresent());
+	}
+}
diff --git a/src/test/java/com/tiedup/remake/rig/anim/modifier/PlaybackTimeModifierRegistryTest.java b/src/test/java/com/tiedup/remake/rig/anim/modifier/PlaybackTimeModifierRegistryTest.java
new file mode 100644
index 0000000..a0640e3
--- /dev/null
+++ b/src/test/java/com/tiedup/remake/rig/anim/modifier/PlaybackTimeModifierRegistryTest.java
@@ -0,0 +1,91 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonPrimitive;
+import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.DataResult;
+import com.mojang.serialization.JsonOps;
+
+import net.minecraft.resources.ResourceLocation;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import com.tiedup.remake.rig.anim.modifier.impl.LoopSectionTimeModifier;
+
+class PlaybackTimeModifierRegistryTest {
+
+	@BeforeAll
+	static void forceClinit() {
+		assertNotNull(LoopSectionTimeModifier.ID);
+		assertNotNull(PlaybackTimeModifierImpl.CODEC);
+	}
+
+	@Test
+	void baseImpl_registered() {
+		assertNotNull(PlaybackTimeModifierRegistry.getCodec(LoopSectionTimeModifier.ID));
+	}
+
+	@Test
+	void getCodec_unknownType_returnsNull() {
+		assertNull(PlaybackTimeModifierRegistry.getCodec(new ResourceLocation("foo", "bar")));
+	}
+
+	@Test
+	void register_duplicateId_throws() {
+		assertThrows(IllegalStateException.class, () ->
+			PlaybackTimeModifierRegistry.register(LoopSectionTimeModifier.ID, LoopSectionTimeModifier.CODEC)
+		);
+	}
+
+	@Test
+	void loopSection_roundtrip() {
+		LoopSectionTimeModifier original = new LoopSectionTimeModifier(0.3F, 0.8F);
+
+		DataResult<JsonElement> encoded = PlaybackTimeModifierImpl.CODEC.encodeStart(JsonOps.INSTANCE, original);
+		assertTrue(encoded.result().isPresent(), "encode error : " + encoded.error());
+		JsonObject json = encoded.result().get().getAsJsonObject();
+		assertEquals("tiedup:loop_section", json.get("type").getAsString());
+
+		DataResult<PlaybackTimeModifierImpl> decoded = PlaybackTimeModifierImpl.CODEC.parse(JsonOps.INSTANCE, json);
+		assertTrue(decoded.result().isPresent());
+		assertEquals(original, decoded.result().get());
+	}
+
+	@Test
+	void loopSection_passthroughWithinWindow() {
+		LoopSectionTimeModifier mod = new LoopSectionTimeModifier(0.3F, 0.8F);
+		Pair<Float, Float> result = mod.modify(null, null, 1F, 0.4F, 0.5F);
+		assertEquals(0.4F, result.getFirst(), 1e-5F);
+		assertEquals(0.5F, result.getSecond(), 1e-5F);
+	}
+
+	@Test
+	void loopSection_wrapsOnOvershoot() {
+		LoopSectionTimeModifier mod = new LoopSectionTimeModifier(0.3F, 0.8F);
+		// elapsed=0.85 → overshoot 0.05 → wrapped=0.35
+		Pair<Float, Float> result = mod.modify(null, null, 1F, 0.82F, 0.85F);
+		assertEquals(0.35F, result.getSecond(), 1e-4F);
+	}
+
+	@Test
+	void dispatchCodec_unknownType_returnsError() {
+		JsonObject json = new JsonObject();
+		json.add("type", new JsonPrimitive("foo:unknown"));
+
+		DataResult<PlaybackTimeModifierImpl> decoded = PlaybackTimeModifierImpl.CODEC.parse(JsonOps.INSTANCE, json);
+		assertFalse(decoded.result().isPresent());
+	}
+}
diff --git a/src/test/java/com/tiedup/remake/rig/anim/modifier/PoseModifierRegistryTest.java b/src/test/java/com/tiedup/remake/rig/anim/modifier/PoseModifierRegistryTest.java
new file mode 100644
index 0000000..32998d3
--- /dev/null
+++ b/src/test/java/com/tiedup/remake/rig/anim/modifier/PoseModifierRegistryTest.java
@@ -0,0 +1,184 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.modifier;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.joml.Quaternionf;
+
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonPrimitive;
+import com.mojang.serialization.DataResult;
+import com.mojang.serialization.JsonOps;
+
+import net.minecraft.resources.ResourceLocation;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import com.tiedup.remake.rig.anim.Pose;
+import com.tiedup.remake.rig.anim.modifier.impl.ChainedPoseModifier;
+import com.tiedup.remake.rig.anim.modifier.impl.JointRotationOffsetModifier;
+import com.tiedup.remake.rig.anim.modifier.impl.JointTranslationOffsetModifier;
+import com.tiedup.remake.rig.armature.JointTransform;
+
+class PoseModifierRegistryTest {
+
+	@BeforeAll
+	static void forceClinit() {
+		assertNotNull(JointRotationOffsetModifier.ID);
+		assertNotNull(JointTranslationOffsetModifier.ID);
+		assertNotNull(ChainedPoseModifier.ID);
+		assertNotNull(PoseModifierImpl.CODEC);
+	}
+
+	// ===== Registry =====
+
+	@Test
+	void baseImpls_registered() {
+		assertNotNull(PoseModifierRegistry.getCodec(JointRotationOffsetModifier.ID));
+		assertNotNull(PoseModifierRegistry.getCodec(JointTranslationOffsetModifier.ID));
+		assertNotNull(PoseModifierRegistry.getCodec(ChainedPoseModifier.ID));
+	}
+
+	@Test
+	void types_returnsThreeEntries_atMinimum() {
+		assertTrue(PoseModifierRegistry.types().size() >= 3);
+	}
+
+	@Test
+	void getCodec_unknownType_returnsNull() {
+		assertNull(PoseModifierRegistry.getCodec(new ResourceLocation("foo", "bar")));
+	}
+
+	@Test
+	void register_duplicateId_throws() {
+		assertThrows(IllegalStateException.class, () ->
+			PoseModifierRegistry.register(JointRotationOffsetModifier.ID, JointRotationOffsetModifier.CODEC)
+		);
+	}
+
+	// ===== Dispatch roundtrip =====
+
+	@Test
+	void dispatchCodec_jointRotationOffset_roundtrip() {
+		JointRotationOffsetModifier original = new JointRotationOffsetModifier(
+			"upper_arm_left", 15.0F, 5.0F, 0.0F
+		);
+
+		DataResult<JsonElement> encoded = PoseModifierImpl.CODEC.encodeStart(JsonOps.INSTANCE, original);
+		assertTrue(encoded.result().isPresent(), "encode must succeed : " + encoded.error());
+		JsonObject json = encoded.result().get().getAsJsonObject();
+		assertEquals("tiedup:joint_rotation_offset", json.get("type").getAsString());
+		assertEquals("upper_arm_left", json.get("joint").getAsString());
+
+		DataResult<PoseModifierImpl> decoded = PoseModifierImpl.CODEC.parse(JsonOps.INSTANCE, json);
+		assertTrue(decoded.result().isPresent(), "decode must succeed : " + decoded.error());
+		assertEquals(original, decoded.result().get());
+	}
+
+	@Test
+	void dispatchCodec_jointTranslationOffset_roundtrip() {
+		JointTranslationOffsetModifier original = new JointTranslationOffsetModifier(
+			"hand_right", 0.0F, -0.05F, 0.02F
+		);
+
+		DataResult<JsonElement> encoded = PoseModifierImpl.CODEC.encodeStart(JsonOps.INSTANCE, original);
+		assertTrue(encoded.result().isPresent());
+		JsonObject json = encoded.result().get().getAsJsonObject();
+		assertEquals("tiedup:joint_translation_offset", json.get("type").getAsString());
+
+		DataResult<PoseModifierImpl> decoded = PoseModifierImpl.CODEC.parse(JsonOps.INSTANCE, json);
+		assertEquals(original, decoded.result().get());
+	}
+
+	@Test
+	void dispatchCodec_unknownType_returnsError() {
+		JsonObject json = new JsonObject();
+		json.add("type", new JsonPrimitive("foo:unknown_mod"));
+
+		DataResult<PoseModifierImpl> decoded = PoseModifierImpl.CODEC.parse(JsonOps.INSTANCE, json);
+		assertFalse(decoded.result().isPresent());
+		assertTrue(decoded.error().isPresent());
+		assertTrue(decoded.error().get().message().contains("foo:unknown_mod"));
+	}
+
+	// ===== Functional behaviour =====
+
+	@Test
+	void jointRotationOffset_missingJoint_isNoOp() {
+		Pose pose = new Pose();
+		JointRotationOffsetModifier mod = new JointRotationOffsetModifier("nope", 45F, 0F, 0F);
+		mod.modify(null, pose, null, 0F, 0F);
+		// No throw ; pose stays empty.
+		assertTrue(pose.getJointTransformData().isEmpty());
+	}
+
+	@Test
+	void jointRotationOffset_rotatesJoint() {
+		Pose pose = new Pose();
+		JointTransform jt = JointTransform.empty();
+		pose.putJointData("head", jt);
+		Quaternionf before = new Quaternionf(jt.rotation());
+
+		JointRotationOffsetModifier mod = new JointRotationOffsetModifier("head", 0F, 90F, 0F);
+		mod.modify(null, pose, null, 0F, 0F);
+
+		// Y component of the quaternion should have changed (90° yaw).
+		assertFalse(pose.get("head").rotation().equals(before, 1e-4F));
+	}
+
+	@Test
+	void jointTranslationOffset_appliesDelta() {
+		Pose pose = new Pose();
+		JointTransform jt = JointTransform.empty();
+		pose.putJointData("hand_right", jt);
+
+		JointTranslationOffsetModifier mod = new JointTranslationOffsetModifier("hand_right", 0.1F, 0.2F, 0.3F);
+		mod.modify(null, pose, null, 0F, 0F);
+
+		assertEquals(0.1F, pose.get("hand_right").translation().x, 1e-5F);
+		assertEquals(0.2F, pose.get("hand_right").translation().y, 1e-5F);
+		assertEquals(0.3F, pose.get("hand_right").translation().z, 1e-5F);
+	}
+
+	@Test
+	void chained_appliesAllModifiersInOrder() {
+		Pose pose = new Pose();
+		JointTransform jt = JointTransform.empty();
+		pose.putJointData("hand_right", jt);
+
+		ChainedPoseModifier chain = new ChainedPoseModifier(java.util.List.of(
+			new JointTranslationOffsetModifier("hand_right", 0.1F, 0.0F, 0.0F),
+			new JointTranslationOffsetModifier("hand_right", 0.0F, 0.2F, 0.0F)
+		));
+		chain.modify(null, pose, null, 0F, 0F);
+
+		assertEquals(0.1F, pose.get("hand_right").translation().x, 1e-5F);
+		assertEquals(0.2F, pose.get("hand_right").translation().y, 1e-5F);
+	}
+
+	@Test
+	void chained_roundtrip() {
+		ChainedPoseModifier original = new ChainedPoseModifier(java.util.List.of(
+			new JointRotationOffsetModifier("head", 10F, 0F, 0F),
+			new JointTranslationOffsetModifier("hand_right", 0F, 0.1F, 0F)
+		));
+
+		DataResult<JsonElement> encoded = PoseModifierImpl.CODEC.encodeStart(JsonOps.INSTANCE, original);
+		assertTrue(encoded.result().isPresent(), "encode error : " + encoded.error());
+		JsonElement json = encoded.result().get();
+
+		DataResult<PoseModifierImpl> decoded = PoseModifierImpl.CODEC.parse(JsonOps.INSTANCE, json);
+		assertTrue(decoded.result().isPresent(), "decode error : " + decoded.error());
+		assertTrue(decoded.result().get() instanceof ChainedPoseModifier);
+	}
+}
diff --git a/src/test/java/com/tiedup/remake/rig/anim/property/AnimationPropertyCodecTest.java b/src/test/java/com/tiedup/remake/rig/anim/property/AnimationPropertyCodecTest.java
new file mode 100644
index 0000000..1c395e4
--- /dev/null
+++ b/src/test/java/com/tiedup/remake/rig/anim/property/AnimationPropertyCodecTest.java
@@ -0,0 +1,248 @@
+/*
+ * © 2026 TiedUp! Remake Contributors, distributed under GPLv3.
+ */
+
+package com.tiedup.remake.rig.anim.property;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.List;
+
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+import com.google.gson.JsonPrimitive;
+import com.mojang.datafixers.util.Pair;
+import com.mojang.serialization.DataResult;
+import com.mojang.serialization.JsonOps;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import com.tiedup.remake.rig.anim.LivingMotion;
+import com.tiedup.remake.rig.anim.LivingMotions;
+import com.tiedup.remake.rig.anim.modifier.PlaybackSpeedModifierImpl;
+import com.tiedup.remake.rig.anim.modifier.PlaybackTimeModifierImpl;
+import com.tiedup.remake.rig.anim.modifier.PoseModifierImpl;
+import com.tiedup.remake.rig.anim.modifier.impl.ConstantFactorSpeedModifier;
+import com.tiedup.remake.rig.anim.modifier.impl.LinearRampSpeedModifier;
+import com.tiedup.remake.rig.anim.modifier.impl.LoopSectionTimeModifier;
+import com.tiedup.remake.rig.anim.property.AnimationProperty.ActionAnimationProperty;
+import com.tiedup.remake.rig.anim.property.AnimationProperty.PlaybackSpeedModifier;
+import com.tiedup.remake.rig.anim.property.AnimationProperty.PlaybackTimeModifier;
+import com.tiedup.remake.rig.anim.property.AnimationProperty.PoseModifier;
+import com.tiedup.remake.rig.anim.property.AnimationProperty.StaticAnimationProperty;
+import com.tiedup.remake.rig.util.TimePairList;
+
+/**
+ * Phase 3 D1 — codec roundtrip and registration tests for the newly-serialized
+ * animation properties (Categories A & B). Pure Java — no MC bootstrap.
+ *
+ * <p>Covers :
+ * <ul>
+ *   <li>Category A trivial codecs : {@code fixed_head_rotation},
+ *       {@code reset_living_motion}, {@code no_gravity_time}, {@code move_time},
+ *       {@code coord_update_time}, {@code coord_start_keyframe_index},
+ *       {@code coord_dest_keyframe_index}</li>
+ *   <li>Category B dispatch codecs : {@code pose_modifier},
+ *       {@code play_speed_modifier}, {@code elapsed_time_modifier}</li>
+ * </ul>
+ */
+class AnimationPropertyCodecTest {
+
+	@BeforeAll
+	static void forceClinit() {
+		// Touch each property so its static field is initialized before any
+		// getSerializableProperty(...) lookup runs.
+		assertNotNull(StaticAnimationProperty.FIXED_HEAD_ROTATION);
+		assertNotNull(StaticAnimationProperty.RESET_LIVING_MOTION);
+		assertNotNull(StaticAnimationProperty.PLAY_SPEED_MODIFIER);
+		assertNotNull(StaticAnimationProperty.ELAPSED_TIME_MODIFIER);
+		assertNotNull(StaticAnimationProperty.POSE_MODIFIER);
+		assertNotNull(ActionAnimationProperty.NO_GRAVITY_TIME);
+		assertNotNull(ActionAnimationProperty.MOVE_TIME);
+		assertNotNull(ActionAnimationProperty.COORD_UPDATE_TIME);
+		assertNotNull(ActionAnimationProperty.COORD_START_KEYFRAME_INDEX);
+		assertNotNull(ActionAnimationProperty.COORD_DEST_KEYFRAME_INDEX);
+		// Bootstrap the modifier registries.
+		assertNotNull(PoseModifierImpl.CODEC);
+		assertNotNull(PlaybackSpeedModifierImpl.CODEC);
+		assertNotNull(PlaybackTimeModifierImpl.CODEC);
+		// Also force LivingMotions clinit so the enum manager knows IDLE etc.
+		assertNotNull(LivingMotions.IDLE);
+	}
+
+	// ===== Category A : trivial codecs =====
+
+	@Test
+	void fixedHeadRotation_registeredAndParses() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("fixed_head_rotation");
+		assertEquals(StaticAnimationProperty.FIXED_HEAD_ROTATION, prop);
+
+		Boolean value = StaticAnimationProperty.FIXED_HEAD_ROTATION.parseFrom(new JsonPrimitive(true));
+		assertTrue(value);
+	}
+
+	@Test
+	void resetLivingMotion_registeredAndParses() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("reset_living_motion");
+		assertEquals(StaticAnimationProperty.RESET_LIVING_MOTION, prop);
+
+		LivingMotion motion = StaticAnimationProperty.RESET_LIVING_MOTION.parseFrom(new JsonPrimitive("idle"));
+		assertEquals(LivingMotions.IDLE, motion);
+	}
+
+	@Test
+	void resetLivingMotion_unknownName_throws() {
+		// parseFrom throws on empty orElseThrow (result is empty because of the error)
+		assertThrows(Exception.class, () ->
+			StaticAnimationProperty.RESET_LIVING_MOTION.parseFrom(new JsonPrimitive("totally_not_a_motion"))
+		);
+	}
+
+	@Test
+	void noGravityTime_registeredAndParses() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("no_gravity_time");
+		assertEquals(ActionAnimationProperty.NO_GRAVITY_TIME, prop);
+
+		JsonArray arr = JsonParser.parseString("[0.1, 0.4, 0.6, 0.9]").getAsJsonArray();
+		TimePairList tpl = ActionAnimationProperty.NO_GRAVITY_TIME.parseFrom(arr);
+		assertNotNull(tpl);
+		// (0.1..0.4) is a no-gravity window ; 0.3 is inside, 0.5 is outside.
+		assertTrue(tpl.isTimeInPairs(0.3F));
+		assertFalse(tpl.isTimeInPairs(0.5F));
+		assertTrue(tpl.isTimeInPairs(0.7F));
+	}
+
+	@Test
+	void noGravityTime_oddLength_codecError() {
+		JsonArray arr = JsonParser.parseString("[0.1, 0.4, 0.6]").getAsJsonArray();
+		// parseFrom calls orElseThrow on an error → any exception is fine.
+		assertThrows(Exception.class, () ->
+			ActionAnimationProperty.NO_GRAVITY_TIME.parseFrom(arr)
+		);
+	}
+
+	@Test
+	void moveTime_registered() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("move_time");
+		assertEquals(ActionAnimationProperty.MOVE_TIME, prop);
+	}
+
+	@Test
+	void coordUpdateTime_registered() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("coord_update_time");
+		assertEquals(ActionAnimationProperty.COORD_UPDATE_TIME, prop);
+	}
+
+	@Test
+	void coordStartKeyframeIndex_registeredAndParses() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("coord_start_keyframe_index");
+		assertEquals(ActionAnimationProperty.COORD_START_KEYFRAME_INDEX, prop);
+
+		Integer value = ActionAnimationProperty.COORD_START_KEYFRAME_INDEX.parseFrom(new JsonPrimitive(3));
+		assertEquals(3, value);
+	}
+
+	@Test
+	void coordDestKeyframeIndex_registeredAndParses() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("coord_dest_keyframe_index");
+		assertEquals(ActionAnimationProperty.COORD_DEST_KEYFRAME_INDEX, prop);
+
+		Integer value = ActionAnimationProperty.COORD_DEST_KEYFRAME_INDEX.parseFrom(new JsonPrimitive(7));
+		assertEquals(7, value);
+	}
+
+	// ===== Category B : dispatch codecs =====
+
+	@Test
+	void poseModifier_registeredAndParses() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("pose_modifier");
+		assertEquals(StaticAnimationProperty.POSE_MODIFIER, prop);
+
+		String jsonText = """
+			{ "type": "tiedup:joint_rotation_offset", "joint": "upper_arm_left", "pitch": 15.0 }
+			""";
+		JsonElement json = JsonParser.parseString(jsonText);
+		PoseModifier mod = StaticAnimationProperty.POSE_MODIFIER.parseFrom(json);
+		assertNotNull(mod);
+		assertTrue(mod instanceof PoseModifierImpl);
+	}
+
+	@Test
+	void poseModifier_unknownType_throws() {
+		String jsonText = """
+			{ "type": "foo:unknown_mod", "joint": "head" }
+			""";
+		JsonElement json = JsonParser.parseString(jsonText);
+		assertThrows(Exception.class, () ->
+			StaticAnimationProperty.POSE_MODIFIER.parseFrom(json)
+		);
+	}
+
+	@Test
+	void playSpeedModifier_registeredAndParses() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("play_speed_modifier");
+		assertEquals(StaticAnimationProperty.PLAY_SPEED_MODIFIER, prop);
+
+		String jsonText = """
+			{ "type": "tiedup:constant_factor", "factor": 0.5 }
+			""";
+		JsonElement json = JsonParser.parseString(jsonText);
+		PlaybackSpeedModifier mod = StaticAnimationProperty.PLAY_SPEED_MODIFIER.parseFrom(json);
+		assertNotNull(mod);
+		// Functional check : given speed=2.0, modifier should return 1.0.
+		assertEquals(1.0F, mod.modify(null, null, 2.0F, 0F, 0F), 1e-5F);
+	}
+
+	@Test
+	void elapsedTimeModifier_registeredAndParses() {
+		AnimationProperty<?> prop = AnimationProperty.getSerializableProperty("elapsed_time_modifier");
+		assertEquals(StaticAnimationProperty.ELAPSED_TIME_MODIFIER, prop);
+
+		String jsonText = """
+			{ "type": "tiedup:loop_section", "loop_start": 0.3, "loop_end": 0.8 }
+			""";
+		JsonElement json = JsonParser.parseString(jsonText);
+		PlaybackTimeModifier mod = StaticAnimationProperty.ELAPSED_TIME_MODIFIER.parseFrom(json);
+		assertNotNull(mod);
+		// Functional check : elapsed=0.9 should wrap back into [0.3..0.8).
+		Pair<Float, Float> wrapped = mod.modify(null, null, 1.0F, 0.85F, 0.9F);
+		assertTrue(wrapped.getSecond() >= 0.3F && wrapped.getSecond() < 0.8F,
+			"wrapped elapsed should be in [0.3..0.8), got " + wrapped.getSecond());
+	}
+
+	// ===== Registry summary =====
+
+	/**
+	 * Integration-ish : after clinit of all the touched properties, the
+	 * dispatch map must contain all 10 new names + the 3 existing D2 names
+	 * + the 3 existing Wave A client-properties names.
+	 */
+	@Test
+	void allNewPropertyNames_registered() {
+		String[] names = {
+			"fixed_head_rotation",
+			"reset_living_motion",
+			"no_gravity_time",
+			"move_time",
+			"coord_update_time",
+			"coord_start_keyframe_index",
+			"coord_dest_keyframe_index",
+			"pose_modifier",
+			"play_speed_modifier",
+			"elapsed_time_modifier"
+		};
+		for (String name : names) {
+			assertNotNull(
+				AnimationProperty.getSerializableProperty(name),
+				"Property '" + name + "' must be registered"
+			);
+		}
+	}
+}