Chess puzzle (Checkmate)
Opening: Alekhine_Defense, Alekhine_Defense_Modern_Variation
Moves: 1. e4 Nf6 2. e5 Nd5 3. d4 d6 4. Nf3 dxe5 5. dxe5 Bg4 6. Be2 e6 7. c4 Nb4 8.
Qxd8+ Kxd8 9. Na3 N8c6 10. Bg5+ Kc8 11. O-O-O Bxf3 12. Bxf3 Nxe5 *
Position (FEN): r1k2b1r/ppp2ppp/4p3/4n1B1/1nP5/N4B2/PP3PPP/2KR3R w - - 0 13
White to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 696
Best move: Rd8#