What is this place?

Hi all:

I died after using the Rynthid Assessment Crystal, and as soon as I landed at my LS, I was immediately portaled to inside the dungeon where my friends were. Then, I was immediately portaled again to some dungeon I didn't recognize. It begins as a small room with a hallway straight ahead, and all there seems to be are three Drudge Wilters before a door that must be killed. Then it's a rinse and repeat. I ended up being critted so I couldn't get too far. I couldn't find Drudge Wilters on the Wiki, so I'm even more curious.

Thanks!

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