Sesa 'Refumee was the leader of the Heretics and taken control of the Gas Mine on Threshold and a small base on Basis, and has Forerunner sentinels as well as 343 Guilty Spark on his side. He and his followers wish to end the Great Journey and discovered that the Prophets are false, the High Prophet of Truth becomes angered of Sesa and sends his new Arbiter, Thel 'Vadam, and lances of Special Operations soldiers to assassinate him and the other Heretics. Vadam fought through waves of Heretic soldiers and Flood forces until he finally confronted Sesa at the Seraph, where the coward planned on escaping. Although outnumbered, Thel managed to kill Refumee and capture 343 Guilty Spark. He is the quaternary antagonist in Halo 2 and serves as the main antagonist for Arbiter's first half, similar to the High Prophet of Regret who was the main antagonist of Master Chief's first half.