Playco cut manual fixes 50% prototyping games with GPT-6 Astra

Using GPT‑6 Astra, the Playco team created an unthemed grey box prototype from simple primitives, and then made a few iterations on gameplay and creative details. From that shared foundation, the team developed three themed game prototypes. Playco says GPT‑6 Astra produced all three in one go.

Most prototypes also worked on the first take. “With Astra, the first prototype was already strong. The only changes we needed to make were based on our gameplay preferences,” said Joao Vieira, Lead Product Engineer. One cyberpunk version needed a performance fix, but the rest came together without additional iteration.

With the previous model, Playco’s initial grey box was less polished. Prompting the model to correct it eventually became counterproductive, so engineers had to step in and fix the game by hand. With GPT‑6 Astra, Playco reports 50% fewer manual fixes.

The team also saw improvements in spatial reasoning, recreating reference images, responsive UI inside Unity, and game feel. Because Playbot can let a model play the game and validate its own changes, Playco says Astra also found bugs more easily and identified places to improve the player experience.

For Playco, the biggest impact is being able to turn more ideas into something developers can play and compare. As lead product engineer Joao Vieira puts it, “If you have 10 ideas for a game, you can do all 10 and actually play them and see how they would feel rather than just imagine.”