Lair bosses

How it works

Lair bosses are marked on your map and need Torment I or higher. You can travel to a lair from its map icon. Summoning a boss is free. Each one leaves a hoard when it dies, and the key is spent opening that hoard. Once the hoard is open, the boss's altar appears again, so you can summon the next fight straight away. In a group, every player needs their own key.

Tiers and keys

Where keys come from

Belial's ambush

When you open a lair boss's hoard there is a chance, roughly one in ten, that Belial ambushes you on the spot. He only ever appears once the hoard is opened, never just from summoning, so he cannot be farmed by summoning a boss over and over. The fight takes place in the Fields of Judgement. Beating him gives Superior Lair Keys, sometimes as many as four at once, and a second round of loot from the boss you just killed. Superior Lair Keys are what open Belial's own hoard.

Loot

Mythics

Since Season 14 any unique can drop as a mythic. Since patch 3.2.1, a mythic from a lair boss or from Belial's hoard comes from that boss's own pool. Initiate bosses now have the same mythic rate as greater bosses, and Belial has the best rate of the lair bosses.

The thirteen iconic mythics below are much rarer. Any lair boss can still drop them.

Other bosses with their own pool

Astaroth and Bartuc also have their own unique pools, but you reach them through Escalating Nightmares and the Infernal Hordes rather than a lair.