Berserker was originally a term for Norse warriors who fought with uncontrollable rage and reckless disregard for their own lives. The term itself is typically translated as "bear's skin" in reference to the animal skins Vikings would wear into battle. Theories about what causes berserkergang, the fury Berserkers go into, include possession by an animal spirit, drunken rage, and ritualistic dancing. Berserkers are often depicted in art as men with crazed eyes biting their shields in anticipation of battle.
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