Chess puzzle (Checkmate)
Moves: 1. Nf3 d5 2. d4 Nf6 3. Nbd2 Bf5 4. Nh4 Bg6 5. Nxg6 hxg6 6. c3 Nc6 7. Qc2 e6 8.
e4 dxe4 9. Nxe4 Nxe4 10. Qxe4 Be7 11. Bd3 a6 12. Bf4 g5 13. Bg3 Qd7 14. O-O-O
O-O-O 15. Rhe1 f5 16. Qxe6 f4 17. Qxd7+ Kxd7 18. Bf5+ Kd6 19. Re6+ Kd5 20. b3
fxg3 *
Position (FEN): 3r3r/1pp1b1p1/p1n1R3/3k1Bp1/3P4/1PP3p1/P4PPP/2KR4 w - - 0 21
White to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 1423
Best move: c4#