Cauldron of Annwn

This Cauldron, though now made into a Chalice, is the true basis of the legend of the Holy Grail of Christian mythology.

Origin
It formed based on the legends of the land of Annwn, in the Otherworld, in which the land was free of disease and is a land of eternal youth, where food was abundant.

Effects
When drank from, it completely restores a person's health and well-being, removing all illness, hunger and thirst as well as reversing the user's age a few years. However, the artifact's power can only be used one time by a person, after which neither they nor their immediate family can use the artifact. If they attempt to drink from the artifact, or if the original drinker attempts a second, they will suffer death which appears to mimic numerous diseases.

Collection
It made its way from Ireland over to England, before reaching Europe in the 1200s. After inspiring the initial legends of the Holy Grail for Christianity, it was found by the Church, who came to accept it as a gift from God. It ended up being part of the Seventh and Eighth Cruscades, when King Louis IX brought it with him in the hopes of increasing his success by using a holy artifact. However, after his death (he had previously used the Grail in the Seventh Cruscade to recover from an injury), it fell into the hands of merchants, who ended up bringing it over to the Byzantine Empire, where it slowly made its way back into Europe and the Holy Roman Empire. Along the way, the merchants realized that this artifact's effects were similar to those which the legendary Holy Grail had, and they turned the Cauldron into a Chalice so that it would sell better. It was collected by Warehouse 8 in 1293 at a remarkably high value.