r1b1kbr1/4pp2/1p3npp/p1qp4/1PPP1B2/N3KP1P/PQ4P1/R4BNR w q - 2 20
FEN state: r1b1kbr1/4pp2/1p3npp/p1qp4/1PPP1B2/N3KP1P/PQ4P1/R4BNR w q - 2 20 ; Best move: b4c5
The current state of the chess board is: Black rook at a8, black bishop at c8, black king at e8, black bishop at f8 and black rook at g8. Black pawn at e7 and black pawn at f7. Black pawn at b6, black knight at f6, black pawn at g6 and black pawn at h6. Black pawn at a5, black queen at c5 and black pawn at d5. White pawn at b4, white pawn at c4, white pawn at d4 and white bishop at f4. White knight at a3, white king at e3, white pawn at f3 and white pawn at h3. White pawn at a2, white queen at b2 and white pawn at g2. White rook at a1, 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 2. Full move number is 20. White to move.