Post-Cutoff

Theo’s ‘FishSlop’ fish-tank game test: Opus 5.5’s best run

Theo - t3.gg (@theo)X109,629 views as of 9 October 2026

Why it is here

Listed in the claudevideo.org community catalog; ~110k views on X by 2026-10-09. Length 1:16.

Made by AI

How we know
X post (2026-09-23): ‘Opus 5.5 had the best run with FishSlop that I’ve ever seen. The animation quality is incredible. The controls feel so much better than any other version I’ve generated. There’s even a complete gameplay loop with a functional in-game economy and unlocks.’
Human role
Theo (t3.gg) runs the same game prompt on each model; this is Opus 5.5’s result.
Pipeline
Opus 5.5 → browser game → 1:16 capture
Series
Agent-built game or 3D world (the video shows the result)

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