Erethon is a Rift Guardian, a greatly empowered Corrupted Angel. He can only be encountered as a random boss in a Nephalem Rift.
In combat, he gains following abilities (as well as increased damage of his melee attack and charge):
- Missile Dampening affix.
- Poison Blast: a delayed (roughly 1.5 seconds) radial blast that highlights the area of effect (roughly 20 yards radius). Damages all enemies around Erethon for average Poison damage.
- Poison Burst: shoots three Poison Bolts in rapid succession, each dealing average Poison damage to a single target.
- Poison Explosion: a delayed (roughly 1.5 seconds) blast that highlights the area of effect (roughly 30 yards radius). Damages all enemies around the casting point (remaining where cast) for high Poison damage. Used when below 50% Life.
With Mara's Kaleidoscope, the battle can be made much easier, especially for melee characters. Erethon also loses the Corrupted Angels' signature adaptive shield.
As of patch 2.1.2, Erethon has received minor changes to his dash attack: the AoE element has been replaced with a ranged attack to give more challenge to ranged characters.
Upon death, Erethon has a chance to drop Amberwing.