Those symbols on his necklace are the Orc number four.
Makes you think.
<--- Warlocks...because DPS is the best form of Crowd Control ----->
how do skulls exist if our bodies aren't real ?
"If you aren't nostalgic of Vanilla WoW, you don't have a heart. If you want to bring it back, you don't have a brain." - Moistmuffins
They're Fel Imp skulls, duh.
I was going to say "shrunken heads", but then it occured to me that irl ritual shrunken heads consist of the soft parts of the head only, the skulls are discarded.
Then again, Draenor is a SAVAGE world of MAGIC and other dickery, I see no reason for an evil warlock to not research a spell to shrink skulls down to a more convenient size.