With the upcoming Warlock Pet Customizations in Patch 10.1.5, Warlock players will finally be able to change the form of their pets with more variants than just certain glyphs. On a recent 10.1.5 PTR hotfix, new customizations were added to the Infernal pet for Destruction Warlocks, and one of them is a long-request one! One of the new Abyssal customizations is a grey and light blue one — That's right, you will be able to customize your Infernal to look like Supremus, the second boss of Black Temple! This is one of the customizations given by learning the Grimoire of the Abyssal — Originally Glyph of the Abyssal, this was a Glyph added during Legion beta, but it never made it live.
The Supremus customization, as well as a fel green and orange Abyssal customization, are unlocked once you learn the grimoire. The technique for the grimoire, Technique: Grimoire of the Abyssal, drops from Gul'dan in Nighthold — In our testing for this post, the grimoire is not a 100% drop, but it can drop from all difficulties, as we obtained it from the LFR difficulty.
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