The Boi-Sen is one of only a small handful of original texts known to date back to the First Chaotic Period. It is a scroll some 45-feet in length made of heavy parchment, and roughly 23% of it was destroyed by fire at some point. The document came from the Boi-Sen Mage Tower, whose location is now lost (probably somewhere east of the Barrier Range, in what later became the Marcon Alliance).
The scroll contains records of the tower, the names and positions of various mages, and, perhaps most importantly, information about Tower Magic and magical practices in general. Mage Wars-era Books of magic are rare, but books of such antiquity are even more uncommon, with only a handful in existence. The Boi-Sen is the oldest such document, and the only one known from that time-period.
Among other data, it includes a recipe for Sorcerer's Sand.
The Boi-Sen is owned by the Gudersnipe Foundation and is kept in archives at the Cultural Anthropology Museum. High-resolution imagery of the document has been made available, but very few scholars from outside the Foundation have been allowed to study it first-hand. Herbet Patric Galactis recounted that his proudest moment as an historian was when he was told the Foundation had granted him permission to see the scroll for himself.
Though the Foundation keeps the scroll under tight security, they make whatever data can be electronically transmitted, freely available for study. As with many such rare artifacts, the Foundation feels that the document's preservation is paramount.