Berserkers

Berserkers are savage fighters found in many societies. They are usually found in many Nordic regions, and are usually members of families and cult members. Two are known and a rumoured third exists. The berserkers themselves are bear worshippers, using the skins of bears, and working themselves up into a fury during battle, being impervious to iron and fire, with their name meaning bear skin. Wolf coats are similar except using & worshipping wolves, while the rumoured boar skins are spoken off as existing but no-one has ever encountered.
Some other societies are hinted to have similar peoples in their armies, mainly other Germanic groups, and it's hinted peoples like the Celts have them too. Humans and Dwarves are the most common berserkers throughout Europe. Many get into such a rage during a battle, all they can do is be pointed at the enemy and let loose. This can terrify an opponent as much as cause severe damage before they are brought down, or tire out becoming lethargic for a few days.

Type

Infantry