This one is inspired by the well known Berserkers from Nordic history who apparently got high af on mushrooms before going into battle.
In the Old Norse written corpus berserkers were those who were said to have fought in a trance-like fury a characteristic which later gave rise to the modern English word berserk (meaning "furiously violent or out of control). It is proposed by some authors that the berserkers drew their power from the bear and were devoted to the bear cult which was once widespread across the northern hemisphere.
In battle the berserkers were subject to fits of frenzy. They would howl like wild beasts foamed at the mouth and gnawed the iron rim of their shields. According to belief during these fits they were immune to steel and fire and made great havoc in the ranks of the enemy. Cute right?