It is a huge construct made up entirely out of cobblestones.

It is a gigantic golem made completely out of cobblestones and containing a binding control spell. Embedded in its chest is a ruby pendant that binds and controls the constuct. The golem looks like a huge humanoid mass of small and medium sized cobblestones.

Combat
It uses the ogre like fighting style of bash bash destroy kill. It follows simple commands and is...well just really good at crushing an enemy. It loves to use it's giant stone club.

Constructs are immune to mind influencing effects and to poison, sleep, paralysis, stunning, disease, death effects, and necromatic effects. They are not subject to critical hits, subdual damage, ability damage, ability drain, or energy drain. They are immune to anything that requires a Fortitude save (unless it also workd on objects). They are not at risk from death from massive damage, but when they are reduced to 0 hit points they are destroyed. Constructs can not be raised or ressurected. Constructs have darkvision with a range of 60 feet.

Society
He is a lone creature and golems don't like anything. They contain no real mind. I mean I guess if the controller of it said

This creature has not yet been play tested.
This is not a kender type creature.