Super Metroid and Castlevania: Symphony of the Night are the one-two punch that made the Metroidvania such beloved game form in the first place, but you could argue that both series were just as good on the GBA - especially on the 'vania side. Since there's a great portable Castlevania collection on Steam, you might think that it would be a perfect fit for Steam Deck.
But as Konami says in a Steam message for the Castlevania Advance Collection: "Before purchasing this software, please be advised that it cannot be played on Steam Deck as it does not support SteamOS." (The same message appears on the Steam page for the Castlevania Anniversary Collection, too.)
The thing is, it seems Konami is absolutely wrong on that point. As demonstrated by the folks at GamingOnLinux, the Castlevania collection boots just fine on Steam Deck thanks to Steam's built-in Proton compatibility features. The games play just fine, too, and save states appear to function without issue.
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