Steam's Remote Play Together feature is out of beta, local multiplayer games are now on sale
Launching after just over a month in beta is Steam's new Remote Play Together feature, which allows Steam users to get together and play local multiplayer games over the internet. All you have to do is start up a game, go over to your friends list, and select a player who you'd like to invite to play multiplayer with. Remote Play Together officially supports up to 4 players at once, but more can join in, though things can get a little laggy if someone's got a bad connection. You can take advantage of playing couch co-op games with others, regardless of platform. All you need is Steam, for Windows, MacOS, or Linux, or alternatively, the Steam Link app for Android/iOS.
Additionally, Steam is also holding a sale specifically focusing on games with local multiplayer, such as Lovers in a Dangerous Spacetime, Overcooked, Towerfall Ascension, and a ton of LEGO games.
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Steam Sale