Alien Hunt

The developers describe how their game uses AI generated content like this:

This is a solo-developed game. Some visual assets were created with the assistance of generative AI. I started from my own sketches and concepts, then used AI to generate and refine artwork, with all final assets reviewed and integrated by me.

Required on Steam store pages since 2024. It covers content that ships in the game, on its store page or in its marketing — Valve does not require a disclosure for AI tools used during development, so this says nothing either way about how the game was made. Check it on Steam.