Joy and I stood there, gaped-jawed, watching as the beast worried away at the stone of the passage, his claws moving in a blur of speed, throwing smoke and dust and stone shards into the air as he went, his scales burning from the friction and growing back as fast as they burned away. He hadn't come far, perhaps five feet toward us, but eventually he would widen the passage enough and pull us out like a badger digging termites out of the nest. I could see now how the fortress had been built without tool marks. The creature moved so quickly - literally wearing away the walls with his claws and scales - that the stone was polished as it was cut.

-Lamb, Chapter 15