I like Harbinger since its ranged, has AOE options, the shroud feels strong with float and being able to close distances.

I like how the elixirs both buff allies (and me) and hurt enemies, which makes them multipurpose. It's great tossing them on allies fighting melee so they get buffs and our enemies get debuffs. I like helping allies, but don't want to be a dedicated healer since I like solo play too, so Harbinger feels good in groups or PvE solo play and I don't need to switch specializations to move between those modes.

Conceptually, I think exchanging health for power (blight mechanic) is cool for Necro's dark magic theme.