Union Alpha on OpenRouter: Tests and Reviews

The author used a Union Alpha 3D game recording as a prompt to rebuild the game in Antigravity with Gemini and in Cursor with Grok 4.6, where Grok won, after Cline with OpenRouter failed to use Union Alpha.

Running a standard shooter prompt on Union Alpha, the stealth model on OpenRouter, produced a fully playable FPS whose menu matches GPT-6 Astra's signature title, orange button and dark 3D scene.

A user typed a single sentence into Union Alpha and got back a playable Mario-like game, which the post frames as a real capability demo beyond benchmark scores.

Someone used Union Alpha to generate a complete, fully playable Super Mario-style platformer in a single file, which the poster calls impressive.

The author says these game demos were all generated by Union Alpha, now free in Grotto Studio, at roughly 1–5 cents per asset, and shares a demo they iterated on.

A developer praised Union Alpha's visual taste, said it would suit iterative game development workflows, and offered to make demos and showcases.

The author used a single prompt in Cline to have Union Alpha build a playable bakery idle simulator, noting it is slow and fails often during the free period but costs nothing.

Given the same low-poly shooter task, Union Alpha produced broken geometry and got stuck, while local DeepSeek V4.1 Flash on two DGX Sparks had full levels, crosshair and kills and cleared three stages.