From Tolkien Gateway
"Berserker" is a concept which has only appeared in an adaptation of the works of J.R.R. Tolkien.

The Orc Berserker was a concept developed for Peter Jackson's film The Lord of the Rings: The Two Towers. The Berserkers are portrayed as a juggernaut-type of Uruk of Saruman with a great two-handed sword. They wear no armor apart from a helmet, and, according to the Weta Workshop designers, they fill it with blood before placing them on their heads and charging into battle, developing a blood-lust.[source?]

A Berserker Uruk-hai is also featured in LEGO: The Lord of the Rings in the set The Battle of Helm's Deep.[1]

Berserker orcs also appear in The Hobbit: The Battle of the Five Armies, although this time they are a type of Gundabad Orcs. They were part of Bolg's second Orc army, and are apparently stronger than the average Gundabad Orc, with some coming close to killing Thorin Oakenshield. Unlike the Uruk berserkers, they wear armor, with some having articulated breastplates resembling faces.[2]