Why is she so evil?

I'm sure this is utterly pointless, but I'll ask anyway: What the hell is her problem?

According to what little we know about her past, she actually had a nice childhood, Rahne took her to Asgard and raised her with her people. We know she wasn't a bad mother because she took good care of Tier once she got her head straight (damn you Rev. Craig and Risman and Cyclops and Wolverine and.....I digress). Anyway, Tier had a much more difficult childhood and he turned out to be a hero, but Rahne gave Vanora every chance she could and she turned out a nasty beast. It was mentioned she grew fast and was full of hate, but that seems a little weird since Tier grew fast, but grew up good like his mom.

Does she have "daddy issues" because Hrimhari was never around? Is that what made Tier better, having his mom and a father figure in Jack?

Well she was already described by her mother as a 'devil spawn'. So the way i see it: sometimes good parents have a child who grows up to be a socio-/psychpath without blame of their own. Since Vanora grew up so quickly i suppose they figured it was part of that. Her hormones raging and didn't realize her condition until it was too late.

Since Peter David is in charge of The All New X-Factor volume, I hope we'll see her into that series.