Chess puzzle (Advantage)
Opening: Kings_Pawn_Game, Kings_Pawn_Game_Kings_Head_Opening
Moves: 1. e4 e5 2. f3 Nc6 3. Bb5 Nf6 4. Ne2 Bc5 5. Nbc3 a6 6. d3 *
Position (FEN): r1bqk2r/1ppp1ppp/p1n2n2/1Bb1p3/4P3/2NP1P2/PPP1N1PP/R1BQK2R b KQkq - 0 6
Black to move.
Themes:  Opening  
Puzzle rating: 1462
Best move: axb5