The long-absent Pokémon Mewtwo finally became available to Super Smash Bros. fans that purchased and registered both the 3DS and Wii U versions of the game yesterday. Unfortunately, it appears as though some players have come across a rather unfortunate glitch regarding the new DLC character.

One of the long-running staples of Smash Bros. series has been the Multi-Man fights where players try to defeat large numbers of generic opponents for high scores. The glitch revolves around the game’s 10-Man Smash. If players have gone through this mode with every other character, and then complete it with Mewtwo, their Global Smash Power (GSP), basically their ranking compared to other players, gets reset to 0, effectively wiping out all of their progress.

Additionally, it appears as though this glitch affects players’ abilities to take part in matches online. Those experiencing the glitches have reported getting an error message saying they can’t go online due to “irregular save data.”

Several different sources have reported this issue, so it doesn’t appear to be small a collection of isolated cases. That said, if you meet the criteria that would leave you open to this glitch, it would be best to avoid 10-Man Smash for a while; at least until Nintendo comes out with a fix for this unfortunate issue.

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