Nf2!! , Rxf2 , Rd1+ , Rf1, Rxf1# explanation: Knight to f2, forcing rook to capture (only move) , rook takes the knight, rook do d1 giving a check, only possible move for white to counter is with rook to f1. And black rook takes white rook on f1 checkmate •Forced Checkmate for black in 3