Chess puzzle (Advantage)
Opening: Queens_Pawn_Game, Queens_Pawn_Game_Accelerated_London_System
Moves: 1. d4 d5 2. Bf4 f6 3. Nf3 g5 4. Bxg5 *
Position (FEN): rnbqkbnr/ppp1p2p/5p2/3p2B1/3P4/5N2/PPP1PPPP/RN1QKB1R b KQkq - 0 4
Black to move.
Themes:  Opening  
Puzzle rating: 876
Best move: fxg5