r1bq1br1/4kp1p/3p2p1/p3p3/1Pp5/2NP1PBP/1PPQP1P1/2R1KBNR w K - 0 18
FEN state: r1bq1br1/4kp1p/3p2p1/p3p3/1Pp5/2NP1PBP/1PPQP1P1/2R1KBNR w K - 0 18 ; Best move: b4a5
The current state of the chess board is: Black rook at a8, black bishop at c8, black queen at d8, black bishop at f8 and black rook at g8. Black king at e7, black pawn at f7 and black pawn at h7. Black pawn at d6 and black pawn at g6. Black pawn at a5 and black pawn at e5. White pawn at b4 and black pawn at c4. White knight at c3, white pawn at d3, white pawn at f3, white bishop at g3 and white pawn at h3. White pawn at b2, white pawn at c2, white queen at d2, white pawn at e2 and white pawn at g2. White rook at c1, white king at e1, white bishop at f1, white knight at g1 and white rook at h1. White kingside is the only castle move available. Half move number is 0. Full move number is 18. White to move.