Nyarraukar

The Nyarroraukar (Q."Demon-rats" S."Nârrogath") or Rat Demon-folk were Greylins or Feadagnir, spirit banes, possessing the essence of warped rodents, often inhabiting corpses.These vindictive, magical creatures were capable of animating a giant, rat-like form composed of the squirming bodies of several hundred living rodents.They were hard to overcome as either their nests (i.e. the corpse) was buried or all the rats forming the body of the Nyarrorauko were destroyed.