|Well, congrats. You discovered it. You get to name it.|
Although this article is based on canonical information, the actual name of this subject is conjectural.
Spontaneous combustion is an event where a target spontaneously catches flames without a visible or natural source. Initially, the target would emit smoke as his or her temperature increases rapidly. Immediately after, flames would appear and grow larger in size. The flames fully engulf the victim, killing the victim in mere seconds. As such it is a very powerful spell utilized by accomplished magic practitioners such as the Thules. Torvald, a Thule, used this to assassinate Isaac Bass, a rabbi who was a member of the Judah Initiative, sworn enemies of the Thules.
Spontaneous combustion is a form of pyrokinesis, although the caster is limited to setting targets on fire, as opposed to creating fire and using it offensively in different forms of attacks.