Zombie Witch lore

Maleficxm Ebonfall, who is better known as Fi Ebonfall, is a demon fairy hybrid.

They have the blood of a witch running through their veins from somewhere along the bloodline, but no one has a clue which side of the family carried it, if they even have a family.
They can't remember anyone, and have been roaming worlds and realms for as long as they can remember.

Fi has to wear a typical witches outfit in order to use the witches magic that they have obtained, due to a fabric that is used on these outfits.
Due to the skull necklace they were around their neck they are able to use dark magics.

They need these specifc items in order to unleash the witches magic that runs within their veins, if they use these magics without these items, catastrophic things could happen.

One day, Fi was determined to practice some of the dark magics that were written down as forbidden to be used again.
They created a humanlike creature, that looked rotten, and overall dead.
It took a few stumbles in Fi's direction, in a panic they kicked it over. The creature was determined for a bite and kept crawling closer and closer until it managed to take a bite from Fi's leg.

The infection didn't take long to set in and within 30 minutes they turned into this zombie like creature, thus starting the downfall of the world that they once knew.