Berserker rakghouls were a mutated strain of rakghouls that existed in the years of the Cold War on the planet Taris. Their notable traits were being more aggressive, violent and vicious to the point that they actively targeted armed convoys in order to feast on organic sentients or infect them with the rakghoul plague.
Their existence came to light to the Sith Empire when researcher Eton Vok observed their activities while studying rakghoul migration patterns and behavior. Vok thus coined the term berserker rakghouls based on their nature. He in turn tasked an Imperial official with eliminating the berserkers before they brought any further damage to Imperial forces.
- Star Wars: The Old Republic (First appearance)