Critical Exchange

Critical Exchange is how a mage with powerful enemies plans their own death.

The caster hands their body to a soul that lost its own, for a term fixed at casting: up to one year per caster level. The tenant lives that life—the face, the name, the house, the debts—while the caster waits out the term as a soul without a body.

Nothing about the body is faked. It eats, ages, bleeds, and dies like the body it is. That is the whole design. When the enemies finally close in, they kill the mage's true body, and every examination they make agrees with them. The dead of this world stay dead (see the diamond), so a file closed this way stays closed.

Divination fails because the body is honestly occupied. A scrying that hunts the caster arrives at the body and finds the tenant answering. There is nowhere else to look. The protection lasts exactly as long as the tenant does: a body they leave, or are driven out of, becomes findable again.

The Return

At the end of the term the caster returns to their body wherever it lies. A tenant still inside is expelled—no Save, no contest.

If the body is dead or destroyed, the caster returns to nothing and stays a soul without a body. Such a soul cannot act on the world and cannot cast, including Vessel, the one spell that would end its condition. Someone else must cast it, or the mage must have arranged it before the exchange. A mage who made no arrangement has traded a death they saw coming for one they cannot leave.

Keeping a corpse intact for that long is its own undertaking. Preserve holds a body for one day per caster level and must be recast, so a twenty-year term is not a spell but an institution: an heir, an order, a sealed vault, and someone still willing to go down there in year nineteen.

False Death buys a single night of the same trick and asks nothing in return.