Kingdom of the Beast: CAT

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

During the development of this game, generative AI tools were utilized to assist in content creation and optimization. The specific use cases are as follows: - Text and Localization: Large language models (such as Gemini and OpenAI) were used to polish the game script and dialogues, as well as to assist with multilingual translation and localization. - Art Assets: AI tools were used to assist in the initial generation and conceptualization of character sprites and CG backgrounds. Subsequently, these assets underwent extensive manual modification, repainting, and refinement by the human developer. All AI-assisted content has been thoroughly reviewed, edited, and verified by the development team prior to release to ensure quality and compliance with all relevant guidelines.

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.