Chess puzzle (Checkmate)
Opening: Caro-Kann_Defense, Caro-Kann_Defense_Two_Knights_Attack
Moves: 1. e4 c6 2. Nf3 d5 3. Nc3 d4 4. Ne2 c5 5. c3 dxc3 6. bxc3 Nc6 7. d4 cxd4 8.
cxd4 Bg4 9. Be3 a6 10. d5 Bxf3 11. gxf3 Ne5 12. f4 *
Position (FEN): r2qkbnr/1p2pppp/p7/3Pn3/4PP2/4B3/P3NP1P/R2QKB1R b KQkq - 0 12
Black to move.
Themes:  Opening Mate in 1 
Puzzle rating: 1619
Best move: Nf3#