1nbqk2r/2pp1pb1/2r1p1pp/pp1P3P/1B3Pn1/2N1P3/PPP3P1/R1QK1BNR w k - 4 15
FEN state: 1nbqk2r/2pp1pb1/2r1p1pp/pp1P3P/1B3Pn1/2N1P3/PPP3P1/R1QK1BNR w k - 4 15 ; Best move: b4a5
The current state of the chess board is: Black knight at b8, black bishop at c8, black queen at d8, black king at e8 and black rook at h8. Black pawn at c7, black pawn at d7, black pawn at f7 and black bishop at g7. Black rook at c6, black pawn at e6, black pawn at g6 and black pawn at h6. Black pawn at a5, black pawn at b5, white pawn at d5 and white pawn at h5. White bishop at b4, white pawn at f4 and black knight at g4. White knight at c3 and white pawn at e3. White pawn at a2, white pawn at b2, white pawn at c2 and white pawn at g2. White rook at a1, white queen at c1, white king at d1, white bishop at f1, white knight at g1 and white rook at h1. Black kingside is the only castle move available. Half move number is 4. Full move number is 15. White to move.