Darksign Curse

One of the worst spells to cast on someone. The target of the spell is trapped inside their own mind. The spell takes the worst aspects of the target, in their own view and that of the caster, and amplifies them. It creates a consciousness that gains control of the, by this point mutated body. The old consciousness is simply along for the ride at that point, seeing what their former body act without any chance to affect it. The original will not die until the body and the new consciousness dies as well.
Someone who's a glutton might be turned into a slavering beast who seeks to eat all it can, which might mean that it eats its former family. The beast itself doesn't care, but the person trapped inside is forced to experience eating its family.

Effect

Transforms the target into a Spawns of Darkness.

Manifestation

A spot of malignancy appears on the target as the spell starts to take effect. As the spell takes hold, the malignancy starts to spread across the body, causing mutations. The exact mutations cannot be predicted until they happen. Depending on the mutation, the subject will experience excruciating pain, generally causing them to scream loudly until they disappear into their own mind, trapped.

Source

The energy to fuel the spell is drawn from the magic energies flowing throughout the world.

Discovery

Discovered in an age long since past by mages worshipping Taika. They studied the effects of magical fluxes and designed the spell to replicate the effects for a more controlled result.

Related Deity/Higher Power

Taika, the Mystic

Material Components

A piece of the target, be it a clump of hair or nail clippings.

Gestures & Ritual

A series of hand gestures and words over a correctly drawn spell circle.

Related School

Pure Magic of Taika

Effect Duration

Permanent