Chess puzzle (Checkmate)
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 4. Ng5 d5 5. exd5 Na5 6. Bb5+ c6 7. dxc6 bxc6 8.
Qf3 Rb8 9. Bd3 Bd6 10. Nc3 h6 11. Nge4 Nxe4 12. Nxe4 O-O 13. Nxd6 Qxd6 14. Bf5
Bxf5 15. Qxf5 Nc4 16. d3 Nxb2 17. O-O Na4 18. Re1 f6 19. Qg6 Qe7 20. Bxh6 Kh8
21. Bd2 f5 22. Re3 Rf6 23. Rh3+ Kg8 24. Qh7+ Kf7 25. Bg5 e4 26. Bxf6 Qxf6 27.
dxe4 *
Position (FEN): 1r6/p4kpQ/2p2q2/5p2/n3P3/7R/P1P2PPP/R5K1 b - - 0 27
Black to move.
Themes: Hanging Piece Endgame Back Rank Mate, Mate in 1 
Puzzle rating: 944
Best move: Qxa1#