Troll 1

Trolls are large, ungainly and vaguely-humanoid creatures that live in and near water. They are not truly amphibious, but they can hold their breath underwater for extended periods of time. They are usually found near rivers, often sheltering in nearby caves, or in caves that feature underground rivers. Trolls possess only rudimentary intelligence, but it is enough to achieve basic communication. Some kings and warlords can convince trolls to join their armies, assuming their couriers can deliver their message before being devoured.