I have some little idea. How about class that would specialize on... Mining? 

And yes - this isn't Vanguardian skin idea. This a new character idea.

I don't have full idea, so I will rework this concept.

What I have now:

Weapon selection - fists. Because we have only one character with fists, and it's very siutable for character that use his hands to borrow.

First skill of this character - burrow. He dig in ground (one block high) and start to guicky move forward under it. With class gem he will controle diraction of burrowing.

Second skill - throw earth. (?) He's simply throw earth block.

And this all by now. 

P.S. I'm thought about his "natural" beome, but I don't have a good idea. Maybe I will try to remake his costume to geode.

P.S.S. I will be happy to hear some more ideas.