What animal is it based on?
Based on the fact that it eats the iron, it may draw inspiration from Pulgasari, a monster which eats iron in Korean legend. It may also be based on a Triceratops and various therapods.
Credit to Bulbapedia. To lazy to link it xP
Stella Midnight actually that is a movie name, I believe the creature you are thinking of is Bulgasari.
http://01072687117.blogspot.com/2013/04/bulgasari.html
Bulgasari is what the creature in the movie is based on.
Everyone thank me later. :p
