r2qkbn1/p1p1p2r/n5p1/3p1P1p/1p1PN2P/1P5b/P1P1PKP1/R1B1QB1R w q - 0 18
FEN state: r2qkbn1/p1p1p2r/n5p1/3p1P1p/1p1PN2P/1P5b/P1P1PKP1/R1B1QB1R w q - 0 18 ; Best move: e4g5
The current state of the chess board is: Black rook at a8, black queen at d8, black king at e8, black bishop at f8 and black knight at g8. Black pawn at a7, black pawn at c7, black pawn at e7 and black rook at h7. Black knight at a6 and black pawn at g6. Black pawn at d5, white pawn at f5 and black pawn at h5. Black pawn at b4, white pawn at d4, white knight at e4 and white pawn at h4. White pawn at b3 and black bishop at h3. White pawn at a2, white pawn at c2, white pawn at e2, white king at f2 and white pawn at g2. White rook at a1, white bishop at c1, white queen at e1, white bishop at f1 and white rook at h1. Black queenside is the only castle move available. Half move number is 0. Full move number is 18. White to move.