History of Hiraks, the Mindbender

Overview

Hiraks, the Mindbender is a Scorn Baron and Ascendant Eliksni obsessed with the Hive. Destinypedia describes him as a former weak Dreg of the House of Exile who fell into the Hellmouth on the Moon and returned changed. He was first fought in Forsaken and returns as the final boss of the Kell's Fall Exotic mission.

Kell's Fall encounter

The fight takes place in the Sanctum of the Revenant Fortress on the Tangled Shore, after the encounters with Araskes, the Trickster and Kaniks, the Mad Bomber. It runs in phases across two planes:

1. In the Revenant Plane (mirror dimension) the Guardian receives the Refracting buff while Hiraks summons Hive and shields himself with Void Ether-Shields. Depleting about a third of his health makes him retreat.
2. In the material plane the Guardian fights through swarms of Thrall and lights three braziers (one in the Revenant Plane, two in the material plane) to reopen the way.
3. Back in the Revenant Plane the Guardian finishes him before a timer expires.

Completing the mission rewards the Slayer's Fang.

Sources disagree

Destinypedia says the first brazier is in the Revenant Plane and the other two in the material plane; the Destiny 2 Wiki says one in the material plane and two in the mirror. Check in game.