From Tolkien Gateway
Mountain-trolls were used by Sauron to wield the great battering-ram, Grond, at the Battle of the Pelennor Fields. Mentioned only once in the written records of Arda, nothing else is known of these creatures. One can only assume that this breed of troll lived in some of the mountains of Middle-earth, and that they were larger than the hill-trolls.
Portrayal in adaptations
1982-97: Middle-earth Role Playing:
- Mountain Trolls are given game statistics, and said to be hostile and rock-throwing.
1995-8: Middle-earth Collectible Card Game:
- "Trolls from the Mountains" is a creature, able to inflict three strikes.
- ↑ J.R.R. Tolkien, The Lord of the Rings, The Return of the King, "The Siege of Gondor"
- ↑ Ruth Sochard Pitt, Jeff O'Hare, Peter C. Fenlon, Jr. (1994), Creatures of Middle-earth (2nd edition) (#2012); note that this breed was not mentioned (as were the other varieties of trolls) in R. Mark Colburn, Peter C. Fenlon, John D. Ruemmler, Terry K. Amthor, Jessica M. Ney (1989), Lords of Middle-earth Vol III: Hobbits, Dwarves, Ents, Orcs & Trolls (#8004)