diff --git a/src/AcDream.Core/Physics/AnimationSequencer.cs b/src/AcDream.Core/Physics/AnimationSequencer.cs
index 9687fea..56e03e4 100644
--- a/src/AcDream.Core/Physics/AnimationSequencer.cs
+++ b/src/AcDream.Core/Physics/AnimationSequencer.cs
@@ -525,7 +525,59 @@ public sealed class AnimationSequencer
         // newly-added node; if preEnqueueTail was null (queue was empty
         // before enqueue), the first new node is _queue.First.
         var firstNew = preEnqueueTail is null ? _queue.First : preEnqueueTail.Next;
-        if (firstNew is not null)
+
+        // #39 Fix B (2026-05-06): for direct cyclic-locomotion →
+        // cyclic-locomotion transitions (Walk↔Run on Shift toggle,
+        // W↔S direct flip, A↔D, Forward↔Strafe), land _currNode on
+        // the new CYCLE (_firstCyclic), NOT on the link (firstNew),
+        // and remove the just-enqueued link from the queue.
+        //
+        // Why: the transition link's drain time (~100–300 ms at
+        // Framerate 30 × link runSpeed) gets restarted before it can
+        // end if the user toggles Shift faster than that. _currNode
+        // sits on a fresh link every UM and Advance never reaches
+        // the cycle. User observes "blips forward in walking
+        // animation" — what they're seeing is the link's
+        // interpolation pose, never the new cycle.
+        //
+        // Conditional on BOTH old AND new being locomotion cycles to
+        // avoid regressing the cases where the link IS the right
+        // animation:
+        //   - Idle (Ready) → any cycle: link is the wind-up pose
+        //   - Falling → Ready: landing animation
+        //   - Ready → Sitting/Crouching: pose-change links
+        //   - Combat substates (attack/parry/ready transitions)
+        // Commit c06b6c5 (reverted in a2ae2ae) demonstrated that
+        // unconditionally skipping the link breaks all of these.
+        //
+        // Retail reference: cdb live trace 2026-05-03 of a Walk→Run
+        // direct transition logged
+        //   add_to_queue(45000005, looping=1)   walk
+        //   add_to_queue(44000007, looping=1)   run
+        // with truncate_animation_list never firing — i.e. retail
+        // appends the new cycle directly without a separate link
+        // enqueue or visible link pose for cyclic→cyclic. Our
+        // structural mismatch was always enqueueing link+cycle and
+        // forcing _currNode onto the link; this fix matches retail's
+        // observed semantics for the locomotion subset.
+        bool prevIsLocomotion = IsLocomotionCycleLowByte(CurrentMotion & 0xFFu);
+        bool newIsLocomotion = IsLocomotionCycleLowByte(motion & 0xFFu);
+        if (prevIsLocomotion && newIsLocomotion && _firstCyclic is not null)
+        {
+            // Drop the just-enqueued link node (firstNew) from the
+            // queue if it's distinct from the cycle — nothing should
+            // ever play it, and leaving stale non-cyclic nodes ahead
+            // of _currNode contributes to the unbounded queue growth
+            // observed in [SCFULL] (qCount climbing past 49 over
+            // ~30 transitions).
+            if (firstNew is not null && firstNew != _firstCyclic)
+            {
+                _queue.Remove(firstNew);
+            }
+            _currNode = _firstCyclic;
+            _framePosition = _firstCyclic.Value.GetStartFramePosition();
+        }
+        else if (firstNew is not null)
         {
             _currNode = firstNew;
             _framePosition = _currNode.Value.GetStartFramePosition();
@@ -1384,6 +1436,20 @@ public sealed class AnimationSequencer
         return result;
     }
 
+    /// <summary>
+    /// True if the given motion-low-byte names a locomotion cycle —
+    /// WalkForward (0x05), WalkBackward (0x06), RunForward (0x07),
+    /// SideStepRight (0x0F), or SideStepLeft (0x10).
+    /// Used by <see cref="SetCycle"/> to recognise cyclic→cyclic
+    /// direct transitions and bypass the transition link in that case
+    /// (retail's observed add_to_queue semantics).
+    /// </summary>
+    private static bool IsLocomotionCycleLowByte(uint lowByte)
+    {
+        return lowByte == 0x05u || lowByte == 0x06u || lowByte == 0x07u
+            || lowByte == 0x0Fu || lowByte == 0x10u;
+    }
+
     /// <summary>
     /// Quaternion slerp matching the retail client's <c>FUN_005360d0</c>
     /// (chunk_00530000.c:4799-4846):