One Quiet Check

An actual selectable chessboard replaces the ASCII board and long move list. Failed moves remain visible; Inspect marks the black king’s escape squares, and Undo returns to the mate-in-one setup.

Tap a white piece, then a highlighted destination to checkmate the black king in one move. Failed trials stay visible; inspect escape squares, then Undo to revise.

Tap or click the controls. Keyboard: Tab and Enter/Space operate every button; arrows/WASD move where available, R restarts, Z undoes calm puzzles.

Mistakes remain revisable. Unlimited undo and restart recover deadlocks.