Terraberserkers were a humanoid species originating from the Cadonian Belt. At least one Terraberserker attended the Festival of Offerings at the Pyramid of the Rings of Akhaten at least once. At the time period at which the Eleventh Doctor and Clara Oswald visited, they were rarely encountered.
One Terraberserker exchanged some form of greeting with the Doctor. The greeting consisted of saying "Qom VoTivig", grunting and shaking their heads in front of each other, hitting each other's left hands with their right one, hitting each other's right hands with their left one, then stretching out their lower bodies. (TV: The Rings of Akhaten)