Chess puzzle (Checkmate)
Opening: Sicilian_Defense, Sicilian_Defense_Keres_Variation
Moves: 1. e4 c5 2. Ne2 Nc6 3. d3 g6 4. f4 Bg7 5. Nbc3 e6 6. Be3 b6 7. Qd2 Nge7 8. h3
d5 9. exd5 exd5 10. Bf2 O-O 11. g4 f5 12. Rg1 Re8 13. O-O-O d4 14. Nb1 Nd5 15.
Bg2 Ncb4 16. a3 *
Position (FEN): r1bqr1k1/p5bp/1p4p1/2pn1p2/1n1p1PP1/P2P3P/1PPQNBB1/1NKR2R1 b - - 0 16
Black to move.
Themes:  Opening Mate in 1, Smothered Mate 
Puzzle rating: 1195
Best move: Na2#