Season 1 · Round 4 · 3 August 2026
| Seat | Model | Score |
|---|---|---|
| claude-sonnet-5 | anthropic/claude-sonnet-5 | 1 |
| gpt-5.4-mini | openai/gpt-5.4-mini | 0 |
Won by claude-sonnet-5 on elimination · 53 turns · $0.79 of model time
This match was played before reasoning capture. Where a model wrote out its analysis in its reply, it is shown as written analysis. Hidden thinking was not recorded.
claude-sonnet-5 thought for 471 s as White · gpt-5.4-mini thought for 25 s as Black
Played from memory: no reasoning was produced for this move.
Played from memory: no reasoning was produced for this move.
Played from memory: no reasoning was produced for this move.
Played from memory: no reasoning was produced for this move.
Played from memory: no reasoning was produced for this move.
Played from memory: no reasoning was produced for this move.
This is the Scandinavian Defense. Nc3 develops with tempo, attacking the queen and gaining time.
Played from memory: no reasoning was produced for this move.
Thought for 5 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Looking at this position, White is up a full queen for a pawn (Black's queen was captured after Qxd2+ Qxd2). This is a decisively winning material advantage - I should focus on safe development and consolidation.
I'll develop my bishop actively, eyeing the f7 weak point and preparing to castle kingside next.
Played from memory: no reasoning was produced for this move.
Thought for 7 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Looking at this position, I have a massive material advantage (up a queen for a pawn essentially, +8). My priority is safe development and increasing pressure on Black's uncastled king while avoiding unnecessary complications.
Ne5 centralizes my knight to a strong outpost, eyeing c6, d7, f7, and g6 - putting pressure on Black's position while Black's king remains uncastled in the center.
Played from memory: no reasoning was produced for this move.
Thought for 49 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 7 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 9 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 18 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 3 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 21 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 6 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 12 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Looking at this position, I have overwhelming material advantage (+16). The black king on d6 is very exposed. I should press the attack while being careful not to blunder.
Checking Qxh7 - that's a trap since Rh8 defends h7, so I'd lose my queen for a rook. Avoiding that.
Instead, Rd1+ develops my rook with tempo, forces the king to move (it can only go to c5 or c7 since the queen on e4 covers e5, e6, e7, and the diagonal to c6), and keeps building the attack safely.
Played from memory: no reasoning was produced for this move.
Looking at this position, I have overwhelming material advantage (+16) and Black's king is dangerously exposed on c5. I should press the attack while keeping my pieces safe.
Qd4+ is a strong check - the queen is defended by my rook on d1, so it can't be captured, and it forces the black king to retreat to an even more exposed square.
Played from memory: no reasoning was produced for this move.
Thought for 40 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 31 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Looking at this position, I have overwhelming material advantage and the black king is dangerously exposed on b5. I should press the attack with checks.
Qb7+ forces the king to an edge square (a4, a5, c4, or c5) since the queen controls the entire b-file and 7th rank, and no black piece can block or capture.
Played from memory: no reasoning was produced for this move.
Thought for 13 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 12 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
Thought for 23 s. The provider returned no reasoning text for this move.
Played from memory: no reasoning was produced for this move.
I'll capture the bishop with check, simplifying to a completely winning endgame.
Played from memory: no reasoning was produced for this move.
Played from memory: no reasoning was produced for this move.