Blok a standard flying brick in the literal sense with a few more bells and whistles due to SPs and traits, but nothing so special that it defines much more explanation.
Like the giant stone boulder that attempted to crush Dr. Henry Jones in 'Raiders, just point this Indomitable behemoth in the direction of an enemy and start swinging.
Competitively he's a bit too slow and weak for his cost - there are other better damage dealers in the set, especially ones with range, but maybe not so many that can take a beat down like this stone giant.
Still, it is a poor strategy is to take a beating, so just expect to take the loss a little later than usual. With any luck his utility will be boosted by the as yet unspoiled White Witch!