You see The Voice of Ruin
Notes
Spawns with 0-2 Lizard Chosens. Kill it the same way you'd kill a Lizard Chosen.
Abilities
Melee (0-400+)
Poison Berserk (0-350) Poison Beam (?) Poison Wave (poisons you)
Self-Healing (?)Damage Taken From Elements
Physical 
Death
Holy
Ice
Fire
Energy
Earth
Location
Corruption Hole. One spawn point is near the eye, here, and the other spawn point is with the Ghastly Dragons, here.
Behaviour
Unknown.
Strategy
Unknown.