Rising through Sokar's ranks, he eventually became one of the four chief henchmen who were tasked with carrying out their master's wishes. Ruax himself was a very feared warrior, often regarded as a true monster, whose primary responsibility was assassinating Sokar's enemies. It was one such mission that led to Ruax's ultimate downfall, as he became so obsessed with hunting down his target that he followed her through an open Stargate without knowing where it led. Once he arrived on the planet, he realized his mistake.
Having stepped unwittingly onto Cimmeria, Ruax was immediately scanned by an Asgard device, and transported into a labyrinth of caves under a nearby mountain while his prey escaped. Ruax soon discovered that he was trapped in the labyrinth, as Thor's Hammer stopped him from escaping. Trapped, Ruax chose to bide his time and wait for someone to free him, surviving by consuming other beings who became trapped with him. His absence from Sokar's side caused turmoil in the System Lord's ranks, as other Goa'uld fought amongst themselves to earn the coveted place at Sokar's side. (RPG: "Fantastic Frontiers: Stargate Season One")
Ruax may have remained trapped if it had not been for the Tau'ri who, deciding to explore a planet which was forbidden by the Goa'uld, sent SG-1 to Cimmeria. The Asgard device at the Gate transported Teal'c, along with Colonel Jack O'Neill who tried to save him from this act, into the labyrinth. Searching the labyrinth, the two Stargate Command personnel soon awaken Ruax who Teal'c identifies as being an Unas. Ruax soon tried to force Teal'c to betray Jack but Teal'c refused, stating that he knew the Goa'uld were false gods. Becoming enraged, Ruax chose to attack the pair but was surprised to find that Jack's weapon still functioned in the labyrinth and was struck down. Though Jack was unconvinced that Ruax was dead Teal'c was, they chose to leave Ruax where he was in order to explore.
Ruax soon revived himself from his wounds, and tracked Jack and Teal'c through the labyrinth before meeting them in the Hall of Mjolnir. Teal'c quickly threw himself against Ruax, encouraging Jack to leave and save himself. Ruax initially overwhelmed Teal'c, but soon the battle was turned as Teal'c managed to force Ruax closer and closer to Thor's Hammer. Though Ruax fought back, Teal'c was able to force him into the hammer which killed both Ruax and his Unas host in a field of painful energy as the host was mortally wounded by Jack and Teal'c shooting him and with Ruax dead, he was unable to recover from his wounds. (SG1: "Thor's Hammer")