From Marduk's Throat

Back to Level 6.

The vizier creates an alchemical substitute for vampiric blood, allowing the drinker of sufficient quantities to decrease her generation. The process converts mercury, molten gold, a range of plant and animal proteins, and other exotic ingredients into vitae. Each ritual, which takes eight hours, produces one fourth of a blood point. To decrease her generation, an Assamite must consume a number of points of this alchemical blood equal to the maximum blood point value of a vampire of the desired generation. (See the chart on Vampire: The Masquerade p. 139.) The consumer of the blood need not be the vizier who prepared the concoction. All of the blood for a given change in generation must be made by the same vizier, in the same laboratory. No more than one week may pass between one use of this ritual and the next for a single drop in generation, or all of the existing vitae elixir spoils.
When the full amount of blood is at hand, the Assamite tries to assimilate the blood into her body. (This is not part of a ritual.) She makes an extended Stamina roll (Difficulty 9), seeking a number of successes equal to the blood points consumed. Failures don’t stop the process, but they do deal 6 points of lethal damage apiece. Assimilation is so painful and distracting that any attacks made against her during this time face a difficulty of only 2.

Errata: In keeping with earlier hints at this ritual, rather than alchemical blood, the subject must consume an equal number of blood points of alchemically modified blood of the desired generation or better. The blood must come from at least three different donors who are actually the generation desired, but the rest can be the alchemically distilled blood of lesser generation vampires - yet another ritual hinted at but never written).