Thel 'Vadam

Arbiter Thel 'Vadam (formerly 'Vadamee) is the Sangheili kaidon of the House of 'Vadam and the last Arbiter to serve the Covenant. He continues to hold this title in the wake of its dissolution. Presently, he leads the Swords of Sanghelios, an alliance of keeps modeled after an ancient order of the same name, and is considered by many to be the formal leader of all Sangheili.

Thel commanded multiple fleets during his service in the Covenant, most notably the Fleet of Particular Justice, of which he was Supreme Commander. This fleet mounted a successful attack on the human colony of Reach under his command and later fought the crew of the UNSC Pillar of Autumn on Installation 04, the first Halo ring to be discovered by the Covenant and humanity. 'Vadamee was responsible for over one billion human casualties over the course of the decades-long war against the humans and the glassing of at least seven colonies. At the outbreak of the Great Schism, Thel became a leading figure among the Sangheili and aided the United Nations Space Command in its efforts to stop the High Prophet of Truth and his forces from activating the Halo Array. He fought in multiple battles alongside the Spartan-II super-soldier, John-117 on Installation 05, Earth, and Installation 00 in the final weeks of the war.

He is an ally of Sonic the Hedgehog and Cloud Strife.