rn5r/2k2q1p/p1bbp1p1/1p2Pn2/Q1Bp2P1/NPP2p1P/PB1P1P2/R2K2NR b - - 5 21
FEN state: rn5r/2k2q1p/p1bbp1p1/1p2Pn2/Q1Bp2P1/NPP2p1P/PB1P1P2/R2K2NR b - - 5 21 ; Best move: b5a4
The current state of the chess board is: Black rook at a8, black knight at b8 and black rook at h8. Black king at c7, black queen at f7 and black pawn at h7. Black pawn at a6, black bishop at c6, black bishop at d6, black pawn at e6 and black pawn at g6. Black pawn at b5, white pawn at e5 and black knight at f5. White queen at a4, white bishop at c4, black pawn at d4 and white pawn at g4. White knight at a3, white pawn at b3, white pawn at c3, black pawn at f3 and white pawn at h3. White pawn at a2, white bishop at b2, white pawn at d2 and white pawn at f2. White rook at a1, white king at d1, white knight at g1 and white rook at h1. Both players have exhausted their castles. Half move number is 5. Full move number is 21. Black to move.