>>513269682
The grail has an inner meaning and outer meaning, and I'll spare you the details but it got tracked to a skull.
In Vajrayana and other tantric schools, a Kapala is central to many rituals. A Kapala is made out of a skull and is Scythian in origin. The Scythians carried them on their belts and made them out of their enemies skulls. In Tantra/Vajrayana they're drank out of and used to make offerings in. A lot of times they're made out of the skulls of masters who pass out of a body.
You can buy real Kapala online for a lot cheaper than you think. If you try to buy a whole skull it'll cost you thousands, a pre-made Kapala is only a couple hundred.