Boulder Beast.
Boulder Beast are armadillo-like creatures with rock hard backs that can roll up into a boulder and steamroll over anyone in its path.
Creature Biology[]
These creatures like rocky areas and they do like to sleep and maybe even be able to feel their way around the world, proven by the fact they can detect invisible greens and easily be woken up by the sound of a footstep of a dwarf landing on dirt. They seem to be employed as unwilling guardians at the Temple Construction Site, guarding long narrow corridors, and taking opportunity to roll over their Dwarven employers.