RefmusePaper

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

RefmusePaper uses generative AI through the Refmuse online workbench to help users create and edit wallpaper images. Live AI generation requires an internet connection, a Refmuse account, and available credits. Users can enter prompts and optionally use reference images to generate or modify wallpaper artwork. Generated content is processed through the Refmuse service and is subject to safety, moderation, and abuse-prevention policies. RefmusePaper may also use AI-assisted sample artwork, screenshots, capsule/library artwork, and promotional materials to represent the wallpaper creation workflow.

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.