In the Halo science fiction universe, the Arbiter is a ceremonial, religious, and political rank bestowed upon alien Covenant Elites. In the 2004 video game Halo 2, the rank is given to a disgraced commander as a way to atone for his failures. Although the Arbiter is intended to die serving the Covenant leadership, the High Prophets, he survives his missions and the Prophets' subsequent betrayal of his kind. When he learns that the Prophets' plans would doom all sentient life in the galaxy to extinction, the Arbiter allies with the Covenant's enemies—humanity—and stops the ringworld Halo from being activated. The Arbiter is a playable character in Halo 2 and its 2007 sequel Halo 3; a different Arbiter appears in the 2009 real-time strategy game Halo Wars, which takes place 20 years before the events of the main trilogy.