Mosstache differs from other fully grown treants in that it has a growth of moss on the lower part of its face, and uses markedly different attacks. In battle, Mosstache lumbers around the camp just performing huge ground pound attacks that damage orcs and level their huts to the ground.
Mosstache is raised from a sapling during the mission Tree Hugger, purely to become an engine of destruction. Mosstache's entire purpose in life is to destroy the huts at Blood Tree Camp, in a bid to stop the orcs from logging in the area. Once its task is complete, Mosstache simply stops and expires.
- The name Mosstache is both a fusion of the words "moss" with "moustache," and a reference to the character Treebeard from The Lord of the Rings (tree and beard become moss and moustache respectively).