Undaunted, the deaf and hard of hearing guild, has defeated Sarkareth on Heroic difficulty and earned the AoTC for Aberrus! Congratulations!
Undaunted is the largest deaf gaming guild in the world with a presence on Area 52 (NA) and Draenor (EU). While the guild is primarily aimed at providing a space for deaf players, they also welcome everyone who wishes to play without the use of voice chat.
Here are shots of both teams earning the AoTC achievement for Aberrus.
NA Raid
EU Raid
Source: Reddit