Chess puzzle (Checkmate)
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bc4 g6 4. d3 Bg7 5. Ng5 d5 6. Bxd5 Nh6 7. O-O O-O 8. c3
Bg4 9. Qb3 Na5 10. Qa4 c6 11. Bc4 Nxc4 12. Qxc4 Be2 13. Re1 Bxd3 14. Qb3 Qe7
15. Nd2 Qxg5 16. c4 Rad8 17. Re3 Bxc4 18. Nxc4 Qg4 19. Rg3 Rd1+ 20. Qxd1 *
Position (FEN): 5rk1/pp3pbp/2p3pn/4p3/2N1P1q1/6R1/PP3PPP/R1BQ2K1 b - - 0 20
Black to move.
Themes: Hanging Piece Middlegame Back Rank Mate, Mate in 1 
Puzzle rating: 420
Best move: Qxd1#