Here is the chronological history of Archmage Ariel Bannister's Sanctum:

21 August 0: Founding and Creation On this date, Archmage Ariel Bannister, the revered head of the Emberfield Academy, established her personal sanctum. This chamber was a testament to her profound magical prowess and dedication to arcane knowledge. A grand floor-to-ceiling stained glass window, her personal creation, adorned the space, each panel intricately depicting a significant triumph in her tireless pursuit of magical understanding.

The sanctum was safeguarded by a unique and powerful ward: a set of enchanted silver bells. These bells were designed to chime not with audible sound, but with pure magical force, serving as an unmistakable alert to any intrusion within the sacred space. Within the heart of the sanctum, the most potent and perilous tomes were securely bound to obsidian pedestals. These dangerous volumes were held fast by chains of pure magical force, a clear demonstration of the volatile knowledge they contained and the precautions taken by the Archmage.

It was within these hallowed walls that Ariel meticulously delved into the forbidden rituals that would eventually guide her path to Stonewatch Island. Her intense studies here ultimately set her on the grim course to confront the infamous Book of Vile Darkness. For a period, the sanctum functioned as a vibrant hub of magical learning and protection, a testament to Ariel's brilliance and foresight.

An Unrecorded Period: Transformation and Desecration Over an unrecorded period, Archmage Ariel Bannister succumbed to the lure of dark power, ultimately transforming herself into a lich. With her transformation, the very essence of the sanctum’s protective magics twisted and corrupted. The enchanted silver bells, once a vigilant guardian, fell silent in the material world.

However, their purpose perverted, the bells now chime ceaselessly on the ethereal plane, their spectral toll serving as an eerie beacon to restless spirits. The powerful knowledge contained within the chained books, once a tool for safeguarding and study, now lies dormant. It waits patiently, poised to be wielded by its corrupted master for purposes of conquest and domination.

Abandonment and Sealing Following Ariel's transformation and the subsequent corruption of its protective enchantments, the sanctum was abandoned in its original purpose. It now stands desecrated, a shadow of its former glory. The chamber has since been magically sealed, its dark secrets and twisted magic locked away from the outside world.

Its current state is one of profound desecration, a chilling reminder of the Archmage's fall from grace. The sealed sanctum remains a monument to both lost knowledge and terrifying power, its ethereal bells eternally chiming a silent warning.