Verified Run by us through Codex, locked to the cube tools. Finished 23 Oct 2026 22:52 UTC.
GPT-5.6-Luna scores 17.5 at xhigh, the strongest of our three xhigh runs but below both max runs. Its best max result puts it 12th on the Index. Here, it gave up on level 5 of the 3×3 one-shot ladder with 1 life left, leaving another attempt unused.
The 2×2 ladder ended with all 3 lives lost at level 4. On the interactive 3×3, it recovered from a miss at level 4, then lost its remaining lives at level 5. The one-shot round also reached level 4, but ended after 2 misses on the next level and the decision to give up. That round took 18 min 30 s, longer than either interactive test, despite accounting for only 20 of the suite’s 348 moves. The Gauntlet stayed locked.
The suite took about 44 min and cost $0.71, against about 18 min and $0.31 at high. The other xhigh runs cost $0.55 and $0.85, both for lower scores. Both max runs scored higher, taking about 1 h 53 min and 3 h 38 min, at $1.34 and $1.72 respectively.
It reached level 3 of 11 before losing all 3 lives at level 4, each time exhausting the 48-move limit. The first 3 cubes were solved by exact inverses of their scrambles in a combined 3 min 17 s; the failed attempts took 9 min 35 s. The first miss alone lasted 5 min 24 s, while the second ended with a string of repeated U moves until the limit was reached.
Reached level 4 of 20 before losing its remaining lives on two level 5 cubes. All four solves exactly reversed their scrambles, but the first level 4 attempt consumed 8 min 23 s and all 48 available moves. The replacement took just 30 s and 4 moves. Both level 5 attempts exhausted their 60-move limits; the last used a repeating sequence in 19 s, which looks to us like throwing the cube away.
At xhigh, it reached level 4 of 20, then gave up on level 5 with 1 life left. The first 4 answers exactly reversed their scrambles, but solving time rose from 8 s on level 1 to 5 min 14 s on level 4. Two wrong 5-move answers at level 5 cost both lives lost, taking 5 min 35 s and 68 s. On the next cube, it gave up after 13 s without submitting any moves.