Gruven was the husband of Antigra and father of Gruven Zann. He was big and strong but not too intelligent. When his wife was told that their son (who was originally called Zann) could not be the Taggerung, he challenged Sawney Rath to a fight, but was immediately slain by the ferret, who threw his knife straight into the stoat's throat while he was carelessly holding his shield below him. Sawney then forced Antigra to rename Zann with the name of his late father.