Spirit Troll

Spirit trolls are immune to being immobilised or stunned and to non-magical weapons. They regenerate health. Can only be killed with fire or acid. When they are attacked by other means they simply collapse until they regenerate enough health to get back up. They have an improved invisibility effect and for that reason cannot be targeted by spells. However, they become visible when they are unconscious. They are much faster, have more HP and regenerate more quickly than other trolls.

They drain Strength every time they hit. This effect is temporary, the lost strength comes back after a couple of minutes.