I can't speak to League of Legends, because I don't play it. On a quick search, it looks like a new "anticheat" method that Riot is introducing is fundamentally incompatible with Linux, because it's kernel level, though 😠 . Honestly, even as a Windows gamer, I'd push back heavily on this new method they're looking to implement, because that's draconian as hell. It is, for all intents and purposes, a rootkit with more privileges than the system administrator account. and it runs even when the game is not, and is not removed when you uninstall their games (instead, you have to uninstall it separately).
Starcraft 3 doesn't exist, but Starcraft 2 plays just fine.
One thing I've noticed over the years is that Linux is the canary in the gaming coal mine, especially at this point. Pretty much any game that isn't actively dis-supported (ie - support and compatibility actively removed) and is simply not written specifically for Linux but uses fairly standard libraries and methods and such, work out of the box. Hell, I played Borderlands 3 the week it launched on Steam without much problem.
So when a game doesn't work on Linux, even if it's not officially supported, 9 times out of 10, it's because the company actively did something to break it. Very often lately, it's been "anti-cheat" software that's overly invasive -- and considering how much flak Acti-Blizz got for Warden being invasive when they first launched it and all of the Acti-Blizz games work just fine on Linux, and Warden pales in comparison to things like Riot's new one, that's saying a ton.
In my opinion, even if you're a die-hard Windows gamer who couldn't possibly care less about the state of gaming on Linux, it's worth seeing what games cannot run at all under Linux, because they're few and far enough between these days that there's a very good chance it's a dead canary and there's something that the publisher is doing that is ethically sketchy.
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