The dwarves of Stonewatch have long had a symbiotic if uneasy relationship with the rock burrowing beasts known as tremor worms. Though few dwarves care to accidentally venture into the lair of one of these creatures, it also cannot be denied that the tunnels left behind by tremor worms have often been used as the basis for new mine shafts.
Growing up to twenty feet long, these powerful creatures can dig through all but the densest of rock. Though not carnivorous by nature, they are known to be highly territorial and will attack anything that invades their domain. Blind and not particularly intelligent, they are highly attuned to vibrations in the ground, which they use to find both potential mates as well as intruders. Indeed, even the most fleet-footed of thieves find it difficult to sneak past them unnoticed.
Tremor worms are covered in a thick, resilient skin covered in granite-like protrusions. This renders them difficult to injure in battle, making their hides greatly prized by armor smiths throughout the vast dwarven kingdom.