Jester Magic | Tyrrapedia: Encyclopedia of Tyrra

Jester Magic is a rather unpredictable and dangerous style of magic that has been outlawed in many lands. It does not use traditional circles of power or components, and instead is fueled by the creativity of the "caster", who in many cases, is not normally capable of casting traditional magic.

Since it's source is unknown, and it cannot be controlled, the results are usually very dangerous. Chances are, if you asked 5 Jester "mages" how Jester magic worked, you would get 5 different answers.