Board Thread:General Discussion/@comment-26489974-20150711090925/@comment-26509603-20150813120021

Adish2004 wrote: Sensei was never referred to as Master Wu or how he got that new outfit, but I think he always had it and wear it since he was going to fight.

Uh, since that outfit looks similar to the Ninja's outfits, he probably ordered his just in case. And, he just plays a bigger role as an Elemental Master in this season, so he gets the title "Master".