Chess puzzle (Checkmate)
Moves: 1. e4 e6 2. d4 f6 3. Nc3 g6 4. f4 Nh6 5. Nf3 Nf7 6. Bc4 Bg7 7. O-O O-O 8. d5 e5
9. fxe5 Nxe5 10. Nxe5 fxe5 11. Rxf8+ Qxf8 12. d6+ Kh8 13. dxc7 Nc6 14. Qd5 Ne7
15. Qf7 a6 16. Qxf8+ Bxf8 17. Nd5 Nxd5 18. exd5 Bd6 19. Bg5 Bxc7 20. d6 Bxd6 *
Position (FEN): r1b4k/1p1p3p/p2b2p1/4p1B1/2B5/8/PPP3PP/R5K1 w - - 0 21
White to move.
Themes:  Endgame Double Bishop Mate, Mate in 1 
Puzzle rating: 498
Best move: Bf6#