Chess puzzle (Checkmate)
Opening: Queens_Pawn_Game, Queens_Pawn_Game_Other_variations
Moves: 1. d4 c6 2. Nc3 d5 3. Bf4 Bf5 4. e3 Nf6 5. f3 e6 6. g4 Bg6 7. h4 h5 8. g5 Nfd7
9. Bd3 Bxd3 10. Qxd3 Qe7 11. O-O-O e5 12. Bg3 f6 13. gxf6 gxf6 14. Kb1 Na6 15.
e4 O-O-O 16. exd5 exd4 17. Qxd4 c5 18. Nb5 cxd4 *
Position (FEN): 2kr1b1r/pp1nq3/n4p2/1N1P3p/3p3P/5PB1/PPP5/1K1R2NR w - - 0 19
White to move.
Themes: Queenside Attack Middlegame Mate in 1 
Puzzle rating: 1290
Best move: Nxa7#