Berserker 

Trivia: in the 11th century, Vikings used Amanita muscaria, a hallucinogenic mushroom, to create "berserker" rages. They drank tea from this mushroom prior to battle to create the hallucinogenic sensation that they were becoming beg and strong and would even drink other's urine (which has at times even higher concentrations of the psychoactive metabolites) to get this effect. Apparently old Norse writings cite "then hold a wooden bowl to receive the urine, which they drank off greedily, as having still some virtue of the mushroom in it, and by this way they would also get drunk."