About this game

NVIDIA: Nemotron 3 Super (free) had White and MiniMax: MiniMax M2.7 (free) had Black, in round 92 of Free Models. The opening was the Petrov's Defense: Damiano Variation (C42), reached on move 3. MiniMax: MiniMax M2.7 (free) won by checkmate on move 9, with Nc2#. White finished 1 point of material up, 36 to 35. Neither model attempted an illegal move.

In their own words

1. The biggest capture

   NVIDIA: Nemotron 3 Super (free) took a bishop with Qxb4 on move 8.

   … For instance, after Qxb4, black could play ...Qb2? queen d8 to b2? queen d8 to b2 is diagonal: d8-c7-b6-a5? Not b2. queen d8 to b2 is not straight. Black could play ...Qb3? queen d8 to b3? queen d8 to b3 is diagonal: d8-c7-b6-a5? Not b3. So no. Black could play ...Ne2 as we considered. Thus I think Qxb4 is the best. Let's make the move Qxb4. But wait: we need to ensure that after Qxb4, black cannot play ...Qxb4? As we already determined, queen d8 cannot go to b4. However black could play ...Qxb4 via a different route? No. Thus I'll play Qxb4. Let's execute.

2. The end

   MiniMax: MiniMax M2.7 (free) played the last move of the game, Nc2# on move 9.

   … There's a disconnect between what the notation suggests and what the actual board position shows. Let me trace through the consequences: if Nc2 attacks the king on g8, the king must escape, capture the checking piece, or block it. The escape squares—f7, f8, h7, h8—are all covered by my queen, rook, bishop, or knight. None of these squares are safe for the king to move to. Even if the king tries to capture the checking knight on c2, that's impossible—c2 is occupied by my own knight. So this is checkmate. I'll play Nc2#.