Mewtwo 10-man Smash Breaks Your Save(s)

[KingWein22]

Be Warned, Smash fans:

Mewtwo can break your game! [http://mynintendonews.com/2015/04/15/the-mewtwo-10-man-smash-glitch-is-causing-problems-online-in-super-smash-bros/]

According to My Nintendo News, Beating 10-Man Smash with Mewtwo can cause your save file to corrupt and prevent you from playing online unless you delete the save.

My Nintendo News:
It looks as though Mewtwo is causing some problems for Super Smash Bros players who wish to play online on Wii U. The problem arises when you clear the 10-Man Smash with all Super Smash Bros characters. If you beat it with Mewtwo you can then corrupt your all-important save data. The GSP for that mini-game is reset to zero. If you then decide to play a game online you are then greeted with this message, ?You have been disconnected because of irregular save data?. The best advice would be to avoid playing 10-Man Smash with Mewtwo until a patch is delivered via Nintendo.

 

[WhiteNachos]

Good to know, is there a way to back up your smash wii u save file?