Vanguard - Idle Auto Battler

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

Some content in this game was created with the assistance of generative AI tools during development, including certain visual assets, store artwork, capsule art, and text. All AI-assisted content was reviewed, edited, and integrated by the developer to ensure it fits the game’s design and overall player experience. Some art assets are sourced from the CC0 asset libraries provided by Kenney. Music and sound effects used in the game are sourced from Phat Phrog Studio and ZapSplat.

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.