Displacement of the Pneuma
A prisoner is suspended inside a frame of copper tubing, secured to it by an elaborate system of leather belts and iron chains. Clamps are placed on the victim's eyelids, forcing them open. Copper clips are clamped onto incisions in the victim's neck, over his heart, kidney and stomach, on his genitals and inside his rectum. Alchemical vapors are wafted onto him, with the aid of a bellows. If the victim passes out from pain or terror, the ritual must be suspended until he recovers consciousness.
An animal, such as a goat or ewe, is lead into the room. It is placed in a cage and also incised at various critical points of its anatomy, and clips attached. The clips connect to catgut strings, which all lead to a simmering vat. The thaumaturge performs incantations to draw the energies of extra-worldly beings into the vat. She ritually "slays" the prisoner by drawing a dull blade across his throat. The blade is hollow and contains a quantity of her own blood; a lever on the trick blade releases the blood, which gushes down onto the victim's chest. The ritual works best if the victim is unaware of the trickery and momentarily believes he's seeing his own throat being slashed.
At this moment, the thaumaturge shouts a word of power into the victim's ear, as loudly as she can. If successful, she shocks the victim's soul out of his body. It travels through the clips, along the cat-gut, into the vat and then out into the body of the animal.
System: One success means that the victim's soul has been separated from the body, but has not traveled into the animal. The victim might as well have been murdered by mundane means. There is no known way to return the soul to the body, although it may linger as a ghost at the storyteller's discretion.
Two successes indicate that the soul has indeed traveled into the animal, but cannot be returned. The victim lives the rest of the animal's lifespan trapped in its body. IT lacks the animal's instincts and may be ill-equipped to survive. A semblance of the victim's intellect, shorn of memory, desire or willpower, remains int he human body. The soulless being is suggestible and follows instructions given by the thaumaturge, but only if they do not require interpretation. It continues to follow the instructions when out of the ritualist's presence, but only for a few minutes. After it realizes that the thaumaturge is no longer present, it simply stops. It either remains standing or curls up on the ground in the fetal position. Without volition, it doesn't even seek its own basic survival and will die of thirst if not ordered to drink.
Three successes allows the thaumaturge to return the victim's soul to his body at the ritual's conclusion. The victim retains no memory of the time his soul spent outside his body. For successes not only allow the soul's return to its body, but permit the victim to report sensations he experienced both in the animal's body and during the transmigration. In each of the latter two cases, the soul remains transgressed for approximately two hours, less ten minutes for each point of the victim's Willpower. The victim's player can nullify the effect entirely by spending Willpower points in excess of the ritualist's dots in Thaumaturgy.
Note: The ritual is a work in progress, the most coherent expression so far of Epistatia's researches into soul migration. She considers it successful if she is able to glean memories and impressions from the victim afterward. She keeps careful notes on these extra-bodily sensations, hoping she will one day be able to use them to design a more complete ritual. Her ultimate aim is to be able to possess a victim's body at will, with no permanent harm to either soul. She continues these investigations out of curiosity, even though the house has found a different replacement for Hermetic immortality. She does not know where they will lead, but is sure there is power in them.