"Lord of the Rings" monster (3)
I believe the answer is:
orc
'lord of the rings monster' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for orc that I've seen before include "Fierce goblin" , "Grampus" , "Giant" , "Sea monster; or Tolkien character" , "Sea-monster" .)