r1bqk1nr/pp1p1p1p/2n1p3/2p3p1/PP5P/N2P1P2/1RPKPbP1/2BQ1BNR w kq - 7 13
FEN state: r1bqk1nr/pp1p1p1p/2n1p3/2p3p1/PP5P/N2P1P2/1RPKPbP1/2BQ1BNR w kq - 7 13 ; Best move: b4b5
The current state of the chess board is: Black rook at a8, black bishop at c8, black queen at d8, black king at e8, black knight at g8 and black rook at h8. Black pawn at a7, black pawn at b7, black pawn at d7, black pawn at f7 and black pawn at h7. Black knight at c6 and black pawn at e6. Black pawn at c5 and black pawn at g5. White pawn at a4, white pawn at b4 and white pawn at h4. White knight at a3, white pawn at d3 and white pawn at f3. White rook at b2, white pawn at c2, white king at d2, white pawn at e2, black bishop at f2 and white pawn at g2. White bishop at c1, white queen at d1, white bishop at f1, white knight at g1 and white rook at h1. Black kingside and black queenside castles are available. Half move number is 7. Full move number is 13. White to move.