Vikus is an Underlander who lives in the royal city of Regalia. He is the grandfather of Luxa, and the husband of Solovet. He is also the head of the Regalian council. Vikus is a diplomat, and focuses much of his time attempting to maintain peacable relations with the many other species of the Underland, most of whom hold him in high regard. He established trade agreements with the spinners, and befriended the gnawer, Ripred. When he was younger, he was an active soldier of the rats.
Vikus strongly believes in Sandwich's prophecies, and immediately identified Gregor as the warrior spoken of in those prophecies. Nevertheless, he was pleased when Gregor initially refused to take Sandwich's sword. Vikus is kind to Gregor and tries to guide him, although he often holds back information if he thinks Gregor is unable to handle it.
Vikus is presented as an "old man," with gray hair. He is estimated to be from his 50s to 60s because he is Luxa's grandfather.
Vikus and Solovet have a fairly rocky relationship. They often argue about how to solve problems, with Solovet clamouring for war, and Vikus trying for peaceful diplomacy. Vikus was devastated when he learned that Solovet had ordered the development of a plague for biological warfare, keeping it a secret even after the plague escaped and contaminated many Regalians. Later, while on a mission, Vikus learns that Solovet is being led into an ambush. He is unable to go after her without jeapordizing Regalia's safety. Solovet is killed by gnawers, and Vikus suffers from a stroke. He recovers physically, but never quite mentally.
Vikus and Solovet had three children. Their daughter, Judith, married the king of Regalia, and both were later killed by gnawers. Judith's twin brother, Hamnet, joined the army at Solovet's insistence. Hamnet was traumatized by a battle and ran away from home. Presumed dead, Vikus and Solovet met him again 10 years later, only to lose him shortly thereafter when Hamnet dies on the quest. Vikus' other daughter, Susannah, married the governor of the Fount.