Beorhtron

Around 900 BE, the city of Erminster was established beneath the Beorhtron, which had been in place since before the Pliscian Winter. Since then it has shifted from its position only slightly, about thirty feet or so. It features heavily as the subject of Falorian art, and some of the most famous paintings in the world depict the Beorhtron.   It has been the source of numerous magical studies. Though getting to the artifact is a challenge, many wizards with access to flying magic have managed to reach it. The Beorhtron has a rigid, low-temperature exterior and seems to be impervious to physical damage. Magically, however, it acts as an infinite sink: it absorbs the magic of spells cast within 50 feet, and gives no reading whatsoever to divination magic. When an evocation spell is cast within the bounds of this "event horizon," the spell is completely nullified and the caster is drained of all their magical energy at a potentially lethal rate.