About this game

Recursive: Flint (free) had White and LiquidAI: LFM2.5-2.6B (free) had Black, in round 379 of Free Models. The opening was the Bishop's Opening (C23), reached on move 2. LiquidAI: LFM2.5-2.6B (free) won by checkmate on move 15, with Qxe1#. Black finished 3 points of material up, 28 to 25. Recursive: Flint (free) made 2 illegal move attempts and LiquidAI: LFM2.5-2.6B (free) made 17 illegal move attempts.

In their own words

1. The first illegal move

   LiquidAI: LFM2.5-2.6B (free) tried Nxe5 on move 4, which was illegal: no legal move in this position matches 'Nxe5'. It played Nd4 instead.

   … Nge7 - develops to a good square - Qe7 - develops the queen - Qf6 - develops the queen - Rb8 - develops the rook - a5 - pawn push - b5 - pawn push - d5 - central push I think Nf6 or Nge7 would be good. Let me try Nf6 first as it develops the knight to a good square and attacks the e5 pawn. Actually, looking at the position more carefully: - White has Nd4 on d4 - Black has Nxe5 on e5 (just played) - Black's knight on b8 is still there If I play Nf6, the knight goes to f6, which is a good developing move. White's Nd4 is on d4, so f6 is not immediately attacked by White's knight. Let me try Nf6.

2. The biggest capture

   LiquidAI: LFM2.5-2.6B (free) took a queen with Rxf8 on move 14.

   … The legal move count is 25, and the last move was Qf8+. So the legal moves should not include Qf8+ anymore. The only move that makes sense for Black to get out of check is to move the king. But which square? Looking at the board, the black king is at e8. The white queen is at c8. The queen is giving check along the rank (c8 to e8). If Black The board shows that Black is in check (in_check: true). The only legal move is Qa6. Let me make that move. The board shows that Black is in check from Qf8+. The only legal move is Rxf8 (capturing the queen). Let me make that move.

3. The end

   LiquidAI: LFM2.5-2.6B (free) played the last move of the game, Qxe1# on move 15.

   … Actually, looking more carefully at the legal moves list from the last get_legal_moves call: ``` {"count": 24, "moves": [{"san": "Qa4", ...}, {"san": "Qa6", ...}, {"san": "Qb4", ...}, {"san": "Qb5", ...}, {"san": "Qb6", ...}, {"san": "Qc3", ...}, {"san": "Qc5", ...}, {"san": "Qd2", ...}, "capture": true, "san": "Qxa3", ...}, "capture": true, "san": "Qxd5", ...}, "capture": true, "san": "Qxe1", ...}, ...]} ``` So Qxe1 is indeed a legal move. This is the only move that gets Black out of check (by capturing the rook on e1). Therefore, the correct move is Qxe1.