Vilefires
Mages who failed training or who flat out rejected it. They're easily spotted by the purple that surrounds their spells, a sign a spell isn't done correctly. They do whatever they want, but to most peoples understanding their goal is to gain power in unconventional or illegal ways. While they started out just as mages who wanted freedom their ranks have few people who have no qualms committing all types of violence to get what they want.
Structure
While most gangs in the circle would fight for control. Vilefires have no issue working towards a common goal. Their leader is whoever has the best plans at the moment. So they have a passing title of Archon in their group.
Public Agenda
To become powerful mages without the shackles of the magical schools.
Assets
Seeing as their name could inspire fear they went looking for something to legitimize their name and skills. They went looking for their namesake, the lost spell of Vilefire. Vilefire was a very old dangerous spell thought to have been created by wizards, brought over by snakes or created in some ancient war effort. Vilefire has a poisonous, sickly green aura around, it comes out like wave of twirling rabid fire, dripping as if it was liquid. Even the stench smells of foul eggs, and burnt remains. When it hits you, your skin becomes numb but your insides feel every movement, every inch feels like your ripping muscles and salting them. Then you heat up until your eyes boil inside of your head and pop. If anyone is touched by the exploding eyeballs, it starts again. It was thought to be lost or abandoned purposely. They searched, bribed, stole and killed their way through anyone they needed to just for scraps of information. Until they found it, and they spent no time wasting it. They killed 3 famous heroes with it, the other bandit groups were on their way to name the new Cyning Bandit. If one of their own hadn't killed the Archon and hid the spell once again.
History
They first appeared around 10 to 12 years ago depending on what story you listen to. It was known that mages who didn't wish to learn at an appropriate pace decided to practice on their own. Of course this isn't illegal, but stealing magical items and breaking into homes and schools to rob others is. Once they were caught all were kicked out the school. From then on they went there own way and recruited anyone who thought in a similar manner. While they started out as just a few rule-breakers, the group has grown to find a sadist and murderers in its ranks. So they are just as dangerous as any other group.
The easiest way to spot a member of this group is when they are trying to rob or possibly kill you. Another is the color of their casting, when spells aren't casted correctly they emit a purple hue around them.