Yana Lialuke
The new GPT-6.1 Terra built Shibuya on Halloween night in three.js for $0.95 in 31 minutes. Claude Opus 5.5, Claude Sonnet 5.5 and Kimi K3.1 Pro got the same brief. Terra was the cheapest and the fastest of the four, while Opus 5.5 had the most cinematic light.
The setup
Every model got the same task, written as a chunked brief, and went through the same stages:
- The main scene – Shibuya at blue hour: the Scramble Crossing, the giant screens, the Hachikō statue, Center-Gai and the view over Tokyo. Each model wrote a plan, the code in chunks, then three rounds of comparing its renders with five reference photos
- Halloween – a costumed crowd: witches, vampires, skeletons, ghosts, pumpkin heads, mummies, with pumpkin lanterns and garlands
- A cosplay close-up and a breakdancer – a Gojo Satoru cosplayer in a close-up at the start, and a breakdancer on Center-Gai
All four worked from the same text, and none saw another model's scene.
- Models: GPT-6.1 Terra, Claude Opus 5.5, Claude Sonnet 5.5, Kimi K3.1 Pro
- Terra and Kimi through OpenRouter, Opus and Sonnet through a Claude subscription
- One scene in plain HTML and three.js, everything generated in code
- Five camera shots, 7 seconds each, recorded the same way for all four
- Test date: Oct 26, 2026
The reference photos came from Wikimedia Commons and were only shown to the models, not used in the scenes.
The numbers
Terra's and Kimi's costs are what OpenRouter billed. Opus and Sonnet ran on a subscription, so their costs are estimates at the API list price.
| Model | Cost | Time |
|---|---|---|
| GPT-6.1 Terra | $0.95 | 31m |
| Claude Sonnet 5.5 | ~$2.30 | 1h 00m |
| Kimi K3.1 Pro | $3.28 | 1h 50m |
| Claude Opus 5.5 | ~$4.90 | 1h 12m |
Terra was about 5x cheaper than Opus by our estimate and 3.5x faster than Kimi. OpenRouter lists it at $1 per million input tokens and $5 per million output. Our full review of the model is in GPT-6.1 Terra: half the price of Sol.
Five shots, four Shibuyas
Each frame below shows Terra and Opus on top, Kimi and Sonnet below.
- GPT-6.1 Terra – the cleanest crossing and readable screens, but a flat grey city in the final view and simple blocky people
- Claude Opus 5.5 – the most cinematic light: wet reflections, glowing screens and light trails across the city at night
- Claude Sonnet 5.5 – the brightest neon and the most colorful crowd, with a soft-focus Hachikō and a pink haze over Tokyo
- Kimi K3.1 Pro – a dense crowd at Hachikō and a sharp crossing, with the plainest buildings and the same grey city view as Terra
The most expensive scene looks the best, and the cheapest one is not far behind on the crossing and the screens.
Our take
GPT-6.1 Terra is the new price and speed leader for this kind of job. It built a full Shibuya with a Halloween crowd for under a dollar, in half an hour. Opus 5.5 still renders the night most like a film, at about five times the price. If you need many scenes fast, Terra is the one to try first.
Sources
- GPT-6.1 Terra on OpenRouter – model page and price
- Claude Opus 5.5 on OpenRouter – the list price we used for the estimate
- Claude Sonnet 5.5 on OpenRouter – the list price we used for the estimate
- Kimi K3.1 Pro on OpenRouter
- Brief, scenes, timings and bills: our test, Oct 26, 2026
