High Prophet of Regret
From Halopedia, the Halo wiki
Summary
The Prophet of Regret is one of three High Prophets that lead the Covenant.
Regret leads the attack on Earth. He lands troops in New Mombasa, East African Protectorate, the only place the Covenant land on Earth. The invasion is foiled, due in part to the actions of the Master Chief, and he then retreats to Delta Halo.
He is finally cornered by the Chief in a temple on Delta Halo in Regret and killed.
He makes a final appearance in the grasp of Gravemind, where he argues with 2401 Penitent Tangent.
Combat
Regret floats around in a hover-chair equipped with a Fuel Rod Cannon-like weapon that fires golden blasts of energy, and is impervious to direct attack. The only way to defeat him is to board his chair and melee attack him.
After a few melee hits, he will throw you off and teleport away, and his chair must be re-boarded to resume the assault. This pattern will repeat until either he or the Master Chief falls.
Regret is not alone, however. Throughout the battle with him, Grunts and Honor Guard Elites will attempt to aid him against the Chief.
Images
http://img137.exs.cx/img137/5946/mediathumb3ga.jpg
