Grok 4.7 vs GPT-6 Astra in 3D scenes

We put the two models on one job: three cinematic Three.js scenes, each a single self-contained HTML file, no textures, no models, no libraries beyond Three.js. A rocket launch with stage separation, a meteor strike that knocks down a city, a dam break that washes away a town.

GPT-6 Astra – @OpenAI, $5/$25 per M tokens on the flex tier via @OpenRouter
Grok 4.7 – @SpaceXAI, shipped Sep 21, $1.6/$4.8 per M tokens via @OpenRouter

- Cost, three scenes
#1 Grok 4.7 – $1.31
#2 GPT-6 Astra – $4.11

- Tries
#1 GPT-6 Astra – 12
#2 Grok 4.7 – 15

- Wall clock, all calls summed
#1 GPT-6 Astra – 25m 14s
#2 Grok 4.7 – 60m 43s

- Output tokens spent on thinking
#1 GPT-6 Astra – ~34% (14–17K per scene)
#2 Grok 4.7 – ~84% (62–86K per scene)

Observations:

• Grok thinks for 17–23 minutes per scene. 79K of its 93K rocket tokens were reasoning. A streaming request goes silent that long: one attempt was cut off and two more hung with zero bytes before a plain non-streaming call got through
• Astra's first rocket had a concrete plain, we asked for grass, and a square bloom halo around the distant stage – both fixed by asking, not by editing. Its meteor only switched the city lights off; "the buildings must physically collapse" was one more request
• Grok's dam break rendered as a white ball. 6,200 spray particles drawn additively on top of a bloom pass, fixed by hand

Grok 4.7 is 3x cheaper per scene and 2.4x slower

Watch the full test via link