Chess puzzle (Checkmate)
Opening: Caro-Kann_Defense, Caro-Kann_Defense_Exchange_Variation
Moves: 1. e4 c6 2. d4 d5 3. exd5 cxd5 4. Nc3 Nf6 5. Bf4 a6 6. h3 Nc6 7. Nf3 Bf5 8. g4
Bg6 9. Nh4 Qb6 10. Nxg6 hxg6 11. Bg2 Qxd4 12. Qxd4 Nxd4 13. O-O-O Nc6 14. Nxd5
O-O-O *
Position (FEN): 2kr1b1r/1p2ppp1/p1n2np1/3N4/5BP1/7P/PPP2PB1/2KR3R w - - 1 15
White to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 940
Best move: Nb6#