Queen mate where the king's own pawns plug the escape squares
A queen delivers mate to a king with the two adjacent escape squares blocked by the king's own pieces. The arrangement looks like a dovetail joint: queen below the king, two friendly pieces hugging the king at the diagonals. Also called Cozio's Mate, after the 18th-century chess composer who catalogued it.
Rook slides to c8. Check on the back rank. The king cannot capture (the rook is too far), and the only legal move is to walk forward.
3 more clean runs (at any point) to reach Recall.
White to move. Black king on g8 with own pawns on h7 and g6 hemming it in. White has a queen on f1 and a rook on c1.
3 more clean runs (at any point) to reach Recall.