Arkanix

Well, she may have been a mutation scrapper to begin with, but after the Embrace (when a vampire drains out your blood and feeds you hers), she may have gained magical powers (the vampire stuff) since the power of the Blood is inherently magical - in most vampire settings anyway.
To back this up in gameplay, buy dual enhancements; Mutation/Magic.
It also makes for a rather intricate backstory.

There's a small group of guys who are of the Changeling: The Dreaming bent with a Super Group styled after House Fiona. We're all recognisable by the 'ap Fiona' after our names.
The roleplaying element should be picking up more once we streamline our online times (one of our guys hasn't been online for 28 days!).
However, I'm all keen for my level 15 magic scrapper, Mauler ap Fiona, to get some RP action.

Indeed, the Tzimisce have an ability called 'Bone Crafting' that goes along with their other abilty, 'Flesh Crafting'. It's all part of a vampire Discipline (Power) called Vicissitude.
Flesh crafting allows the vampire to make flesh maleable like wax or clay. It's usually used for disguises, since you can craft yourself a new face.
Bone crafting allows you to fuse, pull, bend, re-form bones at will. I believe the higher level of the discipline is called Horrid Form - it allows the vampire to sprout huge spines all over their body. It also gives you enormous claws and strangely enough, seven fingers and black, oily skin.
Unfortunately, I'd go for Magic Scrapper rather than mutation scrapper - it's so much easier to explain.
Although, if you've watched Blade 2, you could explain it away as a mutation of the vampire disease.