patch.diff

--- src/controller.ts
+++ src/controller.ts
@@ -589,7 +589,12 @@
              this.actionTimers.down %= SOFT_DROP_SPEED;
              // Cap steps to prevent freeze/tunneling
              // FIX: Latency - optimize maximum sonic drop steps
-             const maxDrop = this.game.getGhostY() - this.game.activPiece.y;
+             // Only calculate getGhostY if we might actually do steps. If steps is larger than game height, cap it.
+             // The maximum drop distance is the playfield height (20) plus hidden rows.
+             if (steps > 22) {
+                 steps = 22;
+             }
+             const maxDrop = Math.max(0, this.game.getGhostY() - this.game.activPiece.y);
              if (steps > maxDrop) steps = maxDrop;

              // Only move down if it's not going to lock immediately