Early in his career, Tartarus served under his uncle Maccabeus on one of the few Jiralhanae-controlled Covenant ships, Rapid Conversion. Rapid Conversion was the ship sent to Harvest to establish first contact with humanity, eventually starting the First Battle of Harvest. During the battle, Tartarus overthrew his uncle, killing him and becoming leader of the clan.
Tartarus’ actions at Harvest caught the eye of the Prophet of Truth, who wanted to replace the Sangheili with the Jiralhanae as leaders of the Covenant military. Over the course of the Human-Covenant War, Tartarus moved up the ranks of the Covenant, eventually being promoted to leader of all the Jiralhanae forces in the Covenant.
As the leading Jiralhanae of the Covenant, Tartarus was involved in many of the final battles of the war. Following the Battle of Installation 04, Tartarus was the one who punished the shipmaster Thel ‘Vadamee, and later followed the Arbiter to the gas giant Threshold to retrieve 343 Guilty Spark. Using the information extracted from Guilty Spark, Tartarus attempted to fire Delta Halo during the Battle of Installation 05. He was killed prior to the ring firing, however, through the combined efforts of the Arbiter, Miranda Keyes, and Sergeant Avery Johnson.