Preserved Caputilation

While it is common for those among the mortal races of Altwaus to fear death, there are those among the lesser races that are so motivated to prevent their own near-certainty of destruction that they stoop to dark magic, rituals, and otherwise forbidden or unwise practices in vain attempts to preserve themselves. One such method is called Preserved Caputilation, and it is performed by layering hundreds of magical enchantments over the subject's head and upper body in a precise, methodical method - before performing a surgical decapitation with a demanding amount of timing and precision over the course of nearly twenty minutes. All while the subject is alive and completely conscious. 
Should the operation fail, the subject's death is guaranteed by the mere act of decapitation. But should the surgical enchantment be successful, the decapitated head will continue to host the subject's consciousness (and arguably their soul) where it can be safely transferred into a variety of different liquid membranes to support the continued oxidation and nourishment of the now severed head. 
Once performed the operation cannot be reversed. The subject is doomed to spend the remainder of their now potentially limitless existence bound forever as a head floating in a liquid membrane usually displayed in a glass jar. A hellish existence for most, there have been unsubstantiated reports that some members of the alvain have preserved particularly useful or frustrating members of the lesser races in this manner, often without their subject's consent. In other cases, the subject may request the operation themselves in an effort to avoid their death by any means necessary. Others still may feel their intellectual work to be far too important to entrust to lesser minds after their natural time of death, and instead elect for operation in a bid to continue their work in a less - albeit in a far more indirect manner.

Utility

The primary goal of Preserved Caputilation is a form a psuedo-immortality. While certainly not truly immortal like an alvain of kinderstarke, there are those among the mortal race that fear the unknown of death enough to risk the operation. While their life afterwards will certainly never be the same, given the proper levels of support and care, a successful performance of a preserved caputilation will ensure the consciousness of the subject matter lives on indefinitely in a preserved state.

Access & Availability

The exact method of performing Preserved Caputilation is a closely guarded secret known by few and taught by even fewer. The practice is banned in nearly all instances across Altwaus and even discussing it will get most arcanist and medical students severely reprimanded. 
Still, there are those among the educated elite who are aware and potentially even practice the specific surgical enhancement. However, admitting it openly would invite a level of social and legal reproach to make flaunting the results of the operation ill-advised.

Complexity

The operation requires a level of arcane and medical knowledge that exists in few minds in Altwaus, and even those who have the knowledge may still lack the skill necessary to perform it successfully. Even a marginal degree of failure would certainly result in the subject's death, leaving a degree of luck required for even the most skilled and practiced hands.