Myrmourn Banshee

"Haaand it ooooover, that thing, youuuuur, magic pooooooower".

The Myrmourn Banshee are one of the three Banshee units in the Nighthaunt - the other two being the Dreadscythe Harridans and Tomb Banshees, and are the closest in appearance to Lady Olynder herself. In life, they were all witches that liked to mess with necromancy, death magic - generally all the nasty eldritch stuff you're not meant to touch. But their mistake was that while they were doing this, they forgot to pay proper respect to Bone Daddy, as is often the case.

Once they died, his punishment for them was essentially the tactic suburban white mothers use when they catch their kids smoking; if you like it so much, you can smoke the whole carton. Only in this case, instead of having to smoke a carton of cigarettes, they have to spend the rest of eternity burdened with an insatiable hunger for magic, having lost literally every other sense and being unable to see anything other than magic and its sources.

Myrmourn Banshees show up as a playable Nighthaunt archetype in the Age of Sigmar Roleplay game.