Some questions about this place

hi there. hope you guys dont get mad because i ask too much, but i have new inquiries about this particular location. it seems to be an abandoned base, with TONS of mobs in it. Maybe ill just show you a screenshot of the moment before i lost haha.

here it is:

okay straight to the point:

- what is really the place all about?
- what do i need to do after having 5000 linkscores?
- how do i even get out of that place(except from surrendering)?

really need some answers because once i know how to go in and out of it, it looks like a good place to grind. thanks in advance.

oh, it's the demon force base (dfb in short). You have one of this in each planet from poyeen all the way to dego (dego got 2). Nothing good drop from this, main goal is to clear it to get the planet's pyroxene or stone fragment (4 to craft into a whole pyroxene).
They are used for crafting various mobs weapon in the lab from that planet correspondingly. With stuff like damtree bazooka from poyeen, grandum launcher from gernia etc.

wow, a short but very informing reply there haha. thanks Mr priskern for the heads up, cause now i just found a reason to stay in gernia longer. these mob weapons look really strong, so im gonna try them out see if it becomes an asset hahaha. thanks again, hope we meet sometime in the game.

- what is really the place all about?
it's the entrace of a dungeon

- what do i need to do after having 5000 linkscores?
you go to the door around the center of the map and enter

- how do i even get out of that place(except from surrendering)?
don't remember if there is a way out

- how do i even get out of that place(except from surrendering)?

You destroy the boss inside the Demon Force Base (cant remember if either it makes you leave after defeating boss or you have to go to the back of the boss room to find the portal to leave)