In the Aberrus raid, several Void references can be found, including in both the Neltharion fight and the final boss fight against Sarkareth!
Patch 10.1 is full of Void and Old God hints so far, such as the N’Zoth fish that’s been discovered, and the ever-present Shadowflame. The Aberrus raid is no different, where several Void references can be found throughout:
A series of void-themed icons with the name “cosmicvoid” have been added.
