diff --git a/src/AcDream.App/Rendering/GameWindow.cs b/src/AcDream.App/Rendering/GameWindow.cs
index 12828de..4d7e278 100644
--- a/src/AcDream.App/Rendering/GameWindow.cs
+++ b/src/AcDream.App/Rendering/GameWindow.cs
@@ -3745,6 +3745,51 @@ public sealed class GameWindow : IDisposable
                         isMovingTo: false,
                         currentBodyPosition: rmState.Body.Position);
                 }
+                // #39 fix-3 (2026-05-06): velocity-fallback cycle refinement
+                // for player remotes. Wire-level evidence (`launch-39-diag2.log`):
+                // when retail's actor toggles Shift while a direction key
+                // is held, retail's outbound MoveToState logic does NOT
+                // emit a fresh packet (only Ready ↔ Run UMs visible in
+                // `[FWD_WIRE]`, despite a clear walk-pace ↔ run-pace
+                // velocity transition in `[VEL_DIAG]`). ACE has nothing
+                // to broadcast → no UM arrives at the observer → cycle
+                // sticks at whatever the last UM set. Compute the
+                // synth-velocity here in the player-remote path AND
+                // call into ApplyServerControlledVelocityCycle, which
+                // routes through the direction-preserving + UM-grace
+                // ApplyPlayerLocomotionRefinement helper (added in
+                // commit 8fa04af).
+                //
+                // The legacy non-player block below (3759+) covers NPCs
+                // and is gated `!IsPlayerGuid`; this block fills the
+                // matching gap for players.
+                if (rmState.PrevServerPosTime > 0.0)
+                {
+                    double nowSecVel = rmState.LastServerPosTime;
+                    double dtPos = nowSecVel - rmState.PrevServerPosTime;
+                    if (dtPos > 0.001)
+                    {
+                        var synthVel = (worldPos - rmState.PrevServerPos) / (float)dtPos;
+                        rmState.ServerVelocity = synthVel;
+                        rmState.HasServerVelocity = true;
+
+                        if (_animatedEntities.TryGetValue(entity.Id, out var aeForVel)
+                            && aeForVel.Sequencer is not null)
+                        {
+                            if (System.Environment.GetEnvironmentVariable("ACDREAM_REMOTE_VEL_DIAG") == "1")
+                            {
+                                System.Console.WriteLine(
+                                    $"[UPCYCLE_SRC] guid={update.Guid:X8} src=synth-player");
+                            }
+                            ApplyServerControlledVelocityCycle(
+                                update.Guid,
+                                aeForVel,
+                                rmState,
+                                synthVel);
+                        }
+                    }
+                }
+
                 // Sync the visible entity to the body — overrides the unconditional
                 // entity.Position = worldPos snap at the top of this function.
                 // For the far-snap branch this is a no-op (body == worldPos); for