Last October, V confirmed that they had begun to troubleshoot Steam's entire library of games so that Steam Deck could run the game. This results in games on Steam being divided into three tabs – Verified (these games are fully optimized for Steam Deck), Playable (these games can run on Steam Deck but may not be fully optimized), and Unsupported (cannot be played on this handheld).
At present, SteamDB has announced the first games of the above three types of games:
Let's look at the unsupported games first, the first list is relatively small, only 5, but there is also a well-known game - Persona 4: Gold Edition. The game page shows that the V Society is still researching to add support, so it is hoped that Persona 4: Gold Edition is not a permanent blacklist.
Then there's the playable tag game, with the first list totaling 24. This includes The Witcher 3, Tomb Raider 9, Tomb Raider: Rise, Neil: The Mechanical Age, Apocalypse of Courage 2, Temple of Heroes, and more. This means that these games can be played on Steam for now, but may encounter some problems.
Finally, there are verified games, with the largest list of the first, with a total of 38. Games that have been fully optimized for Steam Deck include Portal 2, Azure, Hollow Knight, Shame, Cuphead 2, Brain Crew 2, Dark Souls 2, Dark Souls 3, Wolf, Deathgate, Death Stranding, Mad Max, Crimson Knot, Alien: Fire Squad, and the upcoming Total War: Warhammer 3.