Mani

Mani, also called the Monster of the peak or the Door Ward is an old immortal monster, children of the Greys, that sided with the Lords during the war but got enchained by Iena and Osgar to the Mountain of Stars. It's endless task is now to defend the top of the mountain from any living. It is also there to prevent the dead from coming back through the gate to the world of the living.
It's bite does not only kill, it steals your soul and tear it into new fur.
To unchain it to the rock the Lords had to do a contest and cheat, Iena built a chain out of undying light and ask to Mani to chase the light rays, not telling it said rays where a trap, once Mani bitted one, the chain merged with his body and tied him to the mountain forever.
He grew bitter and now hate as much the Lords as he hated the Greys back in the days.