The smaller sub species that came out of the Threat's feet is a small cluster of subterranean carnivorous worm creatures. They dig underground at a little over the speed an average human runs. They go after weak, vulnerable prey too small for the Threat's main attention. So, if you wanna write something about the guy who ran away or the scouts attacking the Threat, and also Thar, you can do that.

You don't have to do all of it. Just the Thar part, really.
Other stuff is just for fun.