=Aeon, The Unbreakable Fortress
Aeon is a Dyson sphere 155 miles in diameter, situated in a pocket dimension temporally displaced at the dawn of creation. The interior of the base is composed of blackened stone, furs, and silver, while the exterior is crafted from rune-engraved dragon scales forged from the blood of gods and the souls of the damned. At its core lies a green and black star that induces madness and frenzied rage in those who gaze into its abyss unprepared. While Aeon is self-maintaining, the fortress is staffed by various fallen angels, demons, and millions of Shoggoth maids.
The outer defenses of Aeon are equally formidable. Aeon possesses a two-mile-long moat of fusing and fissioning plutonium continuously flowing around it. The moat is also home to over one hundred million mutant sharks. Additionally, it has antimatter turrets powered by the souls of sapient black holes, manned by one hundred neutron star golems led by a bound Dark Young and two Hounds of Tindalos.
Should Aeon ever be threatened, it can open portals that bring forth various horrors such as Byakhees of Hastur, Deep Ones, Shoggoths, Nyarlathotep's Favored, Mi-Go, and Elder Things. It also has a wide selection of magical wards, including an alarm ward, a power dampener, and a technology breaker.
Story
Aeon first appears during the events of a Magical Girl ☆Sym-Tan☆ Season 6 Prelude in a heavily destroyed state.
Note
The owner, Lurker, has spent a long time creating and building this overbuilt and ridiculous impenetrable fortress, which involves the corpses of gods and other equally valuable resources.