I've been fighting this warlock named Swizzle of Bladefist and she called me horrible when she teleported on top of the building while she's keep catching me disadvantage. Shooting me down on top of the... let's look at the example
Top Building of Halaa
Top Goldshire Blacksmith or Inn
Top of Any Types of Building that it takes time to reach.
Top of Buildings in NOrthrend or Outland that you need out of combat to reach there.
Even that, we death knights can't pull her off the building, that's the most fustrating thing i've ever seen, i'm just saying that Demonic Circle must be nerfed in some occasions.
That ability is extremely fustrating to melees.
When you cast Demonic Circle, you must be line of sight in it, because it's annoying as hell when the one warlock teleports on top of the building like a wuss, killing melees in their mass disadvantage.
Also, make Death Grip pull of someone on top of the building if you don't like the Demonic Circle suggestion.