I'm in the middle of Mooshu now, and will it get really hard when you try to defeat the boss in the end?
It was moderately hard on my ice wizard, because I was just starting out, but the second time I went around with my Storm wizard, Megan, I soloed everything except Shirataki Temple. It really depends on your strategy, and school.
It really depends on what kind of wizard you are for me (I am death) it was some what hard and in other cases easy also depends on how good you are at the game. And a little tip: tomigowa the evil kill his minion first so he can't hurt you as fast that I my tip for death wizards. From - ________- whale face
Mooshu is a harder world than Marleybone or Grizzleheim because you are advancing in the game but if you start Mooshu at a high enough level, you should be fine. I started Mooshu at level 38 and I had no problems in battle at all.