Xenian upgrade

[Farhood21]

I'm trying to make an "advanced" Xenian. By that I mean, I'm trying to level up without changing class. When talking to the Class change NPC it hints that it's possible to do so, but I wonder how that's possible since you can't leave the beginner areas without changing class. So here are my questions, has anyone tried this? Is there a certain level when I can move on to the harder areas? Is it worth the trouble?

[Acidic]

In the japanese and korean version's there is new skills and stuff for xenian. However, it's currently not in CBT.