Whats are gates in this Universe?? Nucleus, dungeon boss?? Can someone explain this verse...

Gates are essentially portals to dungeons. Dungeons are where monsters live, and they serve as the battlegrounds for guides x esper universes. These dungeons are like video games, where they have a bunch of minions (small mobs/monsters) and a boss (a much bigger and difficult monster) that must be cleared (defeated) to close the gate. These boss monsters drop a nucleus when defeated, which are usually sold at high prices as a type of material. It’s a lot of gamer speak, but hope this helps lol

Thanks. It helps a lot