Outer Thing

The outer things are primordial horrors from deep in The End, though sometimes they can be found deep in the overworld. They have a longer agro range than most mobs and can be avoided, since they hardly see mortals as worth their attention. But get to close and they will attack with three deadly attacks: a cloud of fire, a cloud of poison gas, or a basic projectile that seems to be made of ... err ... no one knows what it is, but its bad. The cloud attacks are slow and easily avoided, but cover a large area and leave obstacles on the battlefield.

Origin

The outer thing were originally made for another mod that was scrapped, and were at first called eldermobs. They are loosely inspired by the iron lich from the game Heretic. Like the fallen angel they were renamed and re-themed to hide their origin. As an alternative to giant metal skulls they were turned into something resembling a Lovecraftian monstrocity, with names derived from "elder thing" and "outer god." It was made intentionally blocky, and a primordial being in the Minecraft universe would probably look like a block.