Goblin

A species of disgusting, violent, ankle-biting cannibals, Goblins are borne of the worst flux of the Changeland and prone to spilling out into other realms and places. No taller on average than a human's knee and with as little merit, Goblins hate all other life and if given nothing else to devour, will resort to ripping up tufts of grass and polluting rivers.

Sirens
Superficially alluring, the Sirens are one of the most pernicious variants of goblin. To their prey, they appear to be the most beautiful creatures imaginable, until they come close enough to rake their prey with iron claws and devour them with distended jaws. They dwell in the Changelands themslves, drawing the unwary and the desperate and trapping them as the terrain shifts.