Voodoo.
An ancient magic, used by the zebras of old to do terrible things. Summoning demons, mind control, and sacrifices meant to appease dark gods were only a few of the things that the evil Witch Doctors are said to do. They could kill by poking a doll, enslave entire towns, and even bring back the dead. It was for these vile reasons that the heroic ponies of old, exploring the savage wilds of Zebrica, led a crusade against the vile cretins once and for all!

At least, that's what they tell you in school. What they don't tell you is that Witch Doctors helped the people come to terms with tragedy, that they could purge negative emotions that would eat away at your soul. They don't tell you that the spirits they summon are mostly amiable, and strong enough to deter great natural disasters, like floods, or wildfires. They don't tell you how much they, no we helped. They definitely don't say that there's still one left.

Her name was Zarya, and she was the world's best Witch Doctor. Now, though, she's dead. Now the world has me. A Witch Doctor in training that'l help you with your feelings, even if I have to beat them up. Someone who'll fight fire with a flood, fight the living with the dead, and save the world by accident.

My name is Zyra, and I'm the world's last Witch Doctor.

Side note: This story is about voodoo, but is in no way an accurate representation. This fictional interpretation of Voodoo is based on that of a webcomic called Vibe (a really good read, if I do say so myself) and as such things may not be accurate. Here's a link to Vibe, for any who want to read it http://www.vibecomic.com/