You can now play Super Mario Maker 2 online with friends, as of the new update today
Those that love Super Mario Maker 2 will be delighted to know that the game's promised post-launch online multiplayer update has just gone live. Version 1.1.0 of the game, which has just gone out through the Nintendo eShop, adds in online multiplayer versus and multiplayer co-op modes, so now you can play Mario Maker courses with your friends, no matter where they are. A much-needed change has also been made to the way that the game checks for online play--prior to starting up an online match, connection stability will be checked, and will cancel the round if the players' connection would cause high latency. Whether this cuts down on the ridiculously slow low-framerate online matches between randoms remains to be seen, but theoretically, it should solve the issue.
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