Vicissitude
Vicissitude is the trademark Discipline of Clan Tzimisce, and one of the most horrifying powers available to Cainite players. With it an experienced crafter can sculpt the flesh and bone of a subject, making them a creature of alien beauty or gnarling them into a deformed monstrosity. Tzimisce use Vicissitude on themselves extensively, altering their appearances with their mood or changing their bodies to be as vile as their souls.
Outside of Thaumaturgy, Vicissitude is the most versatile of the Disciplines, and is often used in tandem with extensive ghouling. Tzimisce tend to deform their servants into war-forms szlachta, which are optimized for combat through extensive bone plating, spiked forearms and other modifications. True masters of fleshcrafting are capable of fusing multiple victims together into mammoth killing machines known as vozhd, but such creations are incredibly rare. Vicissitude was also used to create the playable Blood Brothers bloodline, and their Discipline Sanguinus is a derivation of the Tzimisce character skillset. While its effects are normally permanent, vampire characters of lower generation can heal fleshcrafting transformations over time. Likewise, the clan curse of the Nosferatu cannot be removed through use of Vicissitude.
The nature of Vicissitude ability set is shrouded in in-character mystery, with even the most elder Fiends only speculating as to its origins and true potential. More than just a Discipline, it seems to act as a virus that "infects" other characters through transmission of blood. It is assumed to be invented by the Tzimisce Antediluvian, with some speculating that Vicissitude itself is an extension of the Elder Tzimisce and that it continues to learn and experiment through those that fleshcraft. Tzimisce characters themselves view the control over physical forms granted by the Discipline as proof of their superiority over mortals who are slaves to their bodies. Practitioners of the Path of Metamorphosis go a step further and consider Vicissitude the path to achieve individual evolution and transcendence through a somewhat scientific approach of research and experimentation.
In the Dirty Secrets of the Black Hand sourcebook, Vicissitude was said to be a parasite that originated in the Deep Umbra and was brought back by a Tzimisce named Andeleon. As a disease, it eats away at the body, mind, and soul of an infected individual until they are consumed and taken over by it, becoming a Souleater. Supposedly the Old Clan Tzimisce were the few Fiends able to isolate themselves and avoid becoming infected. The True Black Hand was devoted to wiping out the alien invasion, while at the same time keeping it a secret from the world.
The idea of Souleaters and Vicissitude as an alien plague received a great deal of criticism and was a divisive element of canon. The Vampire Storytellers Handbook Revised stated the idea was merely the result of a "lunatic fringe" within the Old Clan Tzimisce, and to be disregarded. However, the Guide to the Sabbat reintroduced an optional rule with Vicissitude as a disease that can infect anyone that comes into contact with tainted blood. Infection is necessary for learning Vicissitude, and the degree to which one is afflicted influences the difficulty of learning levels of the Discipline. Instead of taking over a practitioner's mind, however, the disease makes it more likely those infected gain a derangement.
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