Board Thread:False Info and Speculative Discussion/@comment-26781694-20160309171151/@comment-26879545-20160518190400

The Benefactor was technically an "evil" banshee. She was juiced up by Peter's coma dreams/goals, sure, but she chose to go through with the plan.

As for the actual mythos of Banshee, it varies, depending on who is asked, but the common theme/aspect is that they show up when someone has either died or is going to die. They are not "evil." There are misconceptions that a Banshee takes pleasure in taking a life, but these "tales" are more common around the U.S.

In Gaelic lore, she is actually grieving for the person about to die and is trying to warn the family that said person is about to die. Normally, (in the mythological sense, anyway) she is only heard, but if one were to see her, then it is the person that sees her that is going to die.

Anyway, there's not really much they can do to make an evil Banshee. In the "original" lore, they're not evil. They're spirits/Faeries that grieve for the soon-to-be dead. In order to make them evil, they'd have to rely on that soul-stealing "Banshee" myth that is featured in the American tales.