Snow Trolls are a species of troll introduced in the Baldur's Gate: Enhanced Edition. They are only found in the Cloud Peaks area which becomes accessible during Rasaad's side quest The Enemies of My Friend.
Like other Trolls, when brought near to death (a minimum of 1 hit point) they fall unconscious to the ground. They can be killed permanently in that state, but only by acid or fire damage, and if not done quickly, they recover heath and consciousness.