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Voidcallers are a type of Voidwalker that look to be draped in old, rotting cloth.^{WoWtBCOSG 331} Voidcallers are spell-casting voidwalkers. They also have two lanterns hanging from the crystals that seem to come from a Naaru of sorts.

This article or section includes speculation, observations or opinions possibly supported by lore or by Blizzard officials. It should not be taken as representing official lore!

When a naaru dies, the light within them slowly bleeds away, leaving void energies in its place. These void energies draw in souls and turns them into creatures of the void while the naaru helplessly watches. This process of spawning these creatures is apparently necessary for, "without the void, the Light cannot exist". Voidcallers may be these dark beings, which are born from dying naaru.

Voidcallers have been seen in Outland where attached to their backs, is something of the sort that looks like the top of a Naaru. These crystals may also have something to do with the Naaru life cycle. It is said that when a Naaru dies, its body turns from pure light into a vortex of dark energies.

It is quite possible that normal (not born from Naaru) Voidwalkers drawn naarus energies, and use the crystals to empower themselves.