The world Eisjer Domain dungeon originally belonged to was something of an Mesozoic or Paleozoic era type of world. Meaning it had no intelligent life form living in it, only wild animals, crazed beasts, and instinctual monsters - something akin to a time period when dinosaurs used to roam on earth.
It was a budding high level of world barely in its diapers, still struggling to grow through the norms of evolution. _when it was pulled by the holes of planes and turned into a dungeon.
As one can take a wild guess with his half dead braincell, the energy of life/evolution stored in such dungeons is super super high. And the unexplored unused resources, infinite.
So when Eisjer first appeared it caused a lot of noise in Arcadia, but due to the suppression of the royal family and combined power of all nobility, the infighting with elites and high guilds came to an end, _Later this dungeon was given to the 2 barons to control.