r1bqk1r1/1p2p1b1/2pp3p/4npp1/Q2N3P/P1PPP3/RP1BKnP1/5BNR w q - 0 15
FEN state: r1bqk1r1/1p2p1b1/2pp3p/4npp1/Q2N3P/P1PPP3/RP1BKnP1/5BNR w q - 0 15 ; Best move: a4b3
The current state of the chess board is: Black rook at a8, black bishop at c8, black queen at d8, black king at e8 and black rook at g8. Black pawn at b7, black pawn at e7 and black bishop at g7. Black pawn at c6, black pawn at d6 and black pawn at h6. Black knight at e5, black pawn at f5 and black pawn at g5. White queen at a4, white knight at d4 and white pawn at h4. White pawn at a3, white pawn at c3, white pawn at d3 and white pawn at e3. White rook at a2, white pawn at b2, white bishop at d2, white king at e2, black knight at f2 and white pawn at g2. White bishop at f1, white knight at g1 and white rook at h1. Black queenside is the only castle move available. Half move number is 0. Full move number is 15. White to move.