The The Skull of Gul'dan was a powerful demonic artifact created from the skull of the orc sorcerer Gul'dan. Used for a plethora of demonic activity, from opening portals to corrupting the forests of Ashenvale, its powers were finally consumed by Illidan Stormrage. Although weakened, the skull still holds power and is in Illidan's possession (for now). Credit to ViciousBambi
How Rare is Skull of Gul'dan?The Skull of Gul'dan drops from Illidan Stormrage. The good news is that the drop rate is relatively high, especially compared to items like the The Twin Blades of Azzinoth. The drop rate so far according to client logging is around 14 %. This is near three times the drop rate of the legendary and we only need the single one. What this means is that most of us that want skull, will have it sooner or later.
Which Class Benefits The Most From Skull of Gul'dan? The MethodThe relative benefit of any item in the game is going to depend on the item that is being replaced, and the players/class performance. Doing this across multiple classes and for everyone’s individual raid setup/performance is going to be impossible. However, if we do some generalizations we can establish a good baseline that can allow us to compare the benefit of giving skull to certain classes, and ultimately which class will see the biggest benefit. Luckily for us (and me writing this guide) all of this comparing has already been done. A group of different class leaders and class discord representatives have collaborated on researching what loot priorities should look like. They have done so for most of the contested phase 3 items, including The Skull of Gul'dan. This theorycrafting has happened over at the Egalitarian Discord and the culmination of
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