Apostate

Apostates are mages who are not part of the Circle of Magi and are thus considered rebel mages. There are two main types of apostates: general apostates, who were never part of the Circle, and rogue mages, who have fled from the Circle. The Templar Order is charged with finding apostates and either capturing or killing them. Maleficarum are the branch of apostate mages considered most dangerous.
The Templar Order is charged with finding apostates and either capturing or killing them. Maleficarum are a branch of apostate mages considered most dangerous.

General apostates

The Templar Order tracks all mages brought to the circle using blood phylacteries. It is entirely possible, however, for a child to be born of two non-magically inclined parents. At a young age, parents will generally sense something is awry in their child. Commotion will arise, often in the community, and Templars will be called forth. This can tear families apart. Some will begin fearing their child, others will begin fearing the idea of their child being taken away.
In these instances, often enough noise will be made to make it to templar ears. They will be tasked with bringing the child to the nearest Circle tower. They will force the child to leave, but will try to accomodate them as best as possible. Rarely does this turn to a malicious or hostile encounter. Even when magical power arises in otherwise unaware adults, the templars try to keep violence and capturing as a last resort.
Those who have fled from the Circle tower are rarely given the same treatment. They are seen as heretics in the eyes of the Chantry, and thus templars are sent to bring them to justice. Usually, this will involve the rogue mage being tracked down using their phylactery until templars slay them. In rare instances, when killing an apostate might be unwanted, they will instead be captured. The Rite of Tranquility would be forced upon them where they become Tranquil, unable to feel emotion or use magic.

Maleficarum

See main article: maleficar.
Maleficarum actively pursue dangerous and forbidden schools of magic, including blood magic. Many apostates do not practice forbidden schools of magic, but the stigma is so intense that most commoners assume that all apostates are maleficarum.