The Vault of Souls
Years before it revealed the secrets of Lichdom to Za’Ul, the Book of Yarta informed a young Mathis Faberman VII about a bit of magic it called the Seal of Eons. The Book described an impossible ritual that could harness the magical energies of the planet and redirect their flow. It would render most of the planet uninhabitable, but provide a wellspring of life to a single region of the planet.
At this time, the known world was a relatively small region known to its inhabitants as, the Garden. All lands beyond the Garden were barren and devoid of workable soil. The people’s of the Garden squabbled over limited natural resources and at its center, lay the City State and kingdom of Yarta.
Mathis deduced that because the city of Yarta was centrally located in the Garden, that it was the epicenter of a Seal of Eons that was older than recorded history.
However, in that decade, Mathis was distracted by mortal ambition. His people were locked in war; he could not concern himself with the wellbeing of the planet. Mathis was desperate for the approval of his family and arcanist peers so he brushed the problem off as something to solve... eventually.
Decades later, the Lich Za’Ul returned to Yarta as a conqueror. He claimed the center of the city for his Tower and his Sanctum and located the Seal of Eons. Za’Ul constructed a device known as The Vault of Souls that made use of dimensional magics to contain the souls of those that perished within his domain. The Book of Yarta instructed that with enough Souls, Za’Ul could shatter the Seal, and return life to the rest of the planet.
Mathis traded his humanity for time. A mortal man became a lich so that he could collect souls across the centuries, not decades. Now centuries later, Za’Ul prepares to spend his amassed fortune and sunder the Seal of Eons.
However, The Book of Yarta has been less than truthful with its keeper. What lies behind the Seal, only it knows (and the Dungeon Master). But that is a post for another day.