GPT-6.1 Terra

GPT-6.1 Terra cleared both interactive ladders at max

GPT-6.1 Terra sits 3rd on the Index, but across seven suites it gave up with lives left 10 times.

Where it stands

GPT-6.1 Terra ranks 3rd of 18 models on the Index, with its best effort, max, scoring 59.0. Just above it is GPT-6-Astra at max, on 87.5.

GPT-6.1 Terra’s Index result cleared all 11 levels of the 2×2 ladder and all 20 of the interactive 3×3, where it could see the cube after turning it. Its one-shot result, one complete answer per cube without seeing the outcome first, stopped after level 6 of 20. No GPT-6.1 Terra run unlocked the 4×4 Gauntlet. Both GPT-6-Astra and Claude Opus 5.5 cleared the one-shot ladder and reached it.

What stood out

We saw GPT-6.1 Terra give up with lives remaining in 10 rounds. Six were interactive rounds at low, medium and high, all abandoned with all 3 lives intact. Even at max, clearing both interactive ladders did not mean it would exhaust its chances on one-shot. One run stopped at level 7 with 3 lives left after spending 19 min 23 s on that round. It said: "Solved through level 6; gave up at level 7." Another max run reached level 8, missed at level 9, then gave up with 2 lives remaining.

At xhigh, GPT-6.1 Terra deliberately used up the move limit on two interactive 3×3 cubes at level 4 to get fresh cubes. It repeated R, a turn of the right face, 40 times on one of them. The two discarded cubes cost 2 lives. GPT-6.1 Terra then solved level 4, but gave up at level 5 with its last life still available. The whole round lasted 100 s and consumed 124 moves.

Effort by effort

• low, 12.6: Reached level 2 on the 2×2 and level 3 on both 3×3 ladders. All three rounds ended by giving up, with only one wrong one-shot answer before stopping.
• medium, 12.6: Matched low’s levels and score. The difference was one-shot: it submitted three unsuccessful answers at level 4 and ran out of lives rather than giving up.
• high, 14.5: Added one solved 2×2 level, reaching level 3 on every ladder. Both interactive rounds ended at level 4 by giving up; three misses there ended one-shot.
• xhigh, 30.5: Cleared the 2×2 with 2 lives left, using 435 moves across the round. The interactive 3×3 stopped after level 4; one-shot again lost every life at level 4.
• max, three runs, 59.0, 62.0, 60.5: Cleared both interactive ladders every time; one-shot stopped after levels 6, 8 and 7, respectively. One interactive level-11 cube took 125 moves against an 11-move scramble.

Time and cost

The max suite used for GPT-6.1 Terra’s Index result took 58 min 5 s. Across all seven suites, time ranged from 61 s at low to 1 h 15 min 25 s for the longest max run. API-equivalent costs are unavailable, so we cannot name a cheapest effort. No lower effort finished close to max: xhigh took 10 min 9 s but stopped 16 levels earlier on the interactive 3×3. Moving from low to medium added 33 s without adding a solved level.