They might seem cruel and savage, perhaps even evil given their alliance with the Lich King. But if you look deeper you will finda rich culture.
Let us look at some of their own words.
"I will eat your heart."
While this might sound like a threat, it is in fact, an expression of love. They wish to consume your heart, the center of love, and so by that, consume your love. They want to have your love. And as we are what we eat, they wish to be your love.
"Your entrails will make a fine necklace."
CLearly they have a much different sense of fashion. In this case, they are practical. In a state of war, it is handy to have a ready source of food, 'rope', or backup organs.
"I will feed you to the dogs."
Keeping dogs well-fed is a sign of both understanding of a companion species' needs and also an expression of affection for the species. After all, if they were being selfish they would be threatening to eat you themselves, like the trolls do.
"No, I can do better, I can..."
They do not give up, they are not quitters. This determination is admirable.
I hope we can all learn to better understand this race and its culture. Maybe someday we will no longer judge them for their decision to join with the current leading nominee for Most Evil Being in Azeroth.
1 hour ago