The aptly named 33 Immortals is in closed beta until June 2nd ahead of its full release. While the beta and subsequent early access release will be used to tailor the game to the community, some things are already set in stone.
33 Immortals – Announcement Trailer
Below are all the confirmed platforms you can play 33 Immortals on, and there is some speculation as to whether the list will be expanded in the future.
Wikipedia and Google's knowledge panel for 33 Immortals both have a platform list, but the list doesn't quite match up with that of the game's website. Wikipedia lists the Xbox One as one of the places you can play the game, but Thunder Lotus Games (the developer) and the Xbox Store only list the current-gen Xbox Series X and S.
While it seems that Xbox players will need one of the newest consoles for this game, that's not the only place you can play. At the time of writing, 33 Immortals is releasing on the following platforms:
