Valve has verified 5,000 games to play on Steam Deck, and another 2,000 are not supported
A “proven” game means that players won’t run into all sorts of outrageous issues with Steam Deck’s native 1280×800 screen resolution (ignoring the innocuous bugs).
In addition, games that are determined to be “playable” need to have solid controller control support and, where necessary, support for on-screen keyboard interaction, compared to “unsupported” games.
It should be pointed out that since Steam Deck runs SteamOS,WindowsGames running on the platform also need to be checked by Valve for a good match with the Proton Compatibility Layer.
In the end, the number of 5,000 games is already quite staggering, and Valve has obviously put a considerable amount of effort behind it. But even if the game has not been certified, it does not prevent players from forcibly trying a wave on Steam Deck.