User blog comment:Lord of Noobs/Could the Colossal Titan be a Wall Titan?/@comment-5433366-20140906202944/@comment-5433366-20140907034020

Yeah that's pretty canon, but I'd say something like mini-Shifters.. haha

But it seems as if they're being controlled against their will to do this stuff from the bidding of those outside the Walls, I think..