Super Smash Bros. Melee didn’t ship with online features—it released in 2001 exclusively for the GameCube. The Dolphin emulator changed that, allowing players to compete online in what is still considered the best competitive Smash game.

Those online features are now greatly improved thanks to the development of Slippi, a fan-made plug-in for Dolphin. It has an impressive features list, but most important is the implementation of rollback netcode, which is considered basically mandatory for competitive online fighters due to its efficiency at eliminating lag and input delay.

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