Swarf was the eldest son of Grekk. He had blond hair. He and his brothers were left on an unnamed planet by their father, where they waged war against the planet's other inhabitants (urged on by Deemon), keeping their captured enemies in the Pit.
When the First Doctor arrived in their castle, Swarf ordered his brother Morag to take him to the Pit. He and his brothers later tried to kill their prisoners when they detected a radio transmission from them to the Crustians, but were caught in a trap in prisoners had made. The Doctor hoped that the sons of Grekk, now prisoners themselves, would rethink the need for peace on their world. (PROSE: The Sons of Grekk)