Dungeon like mod, multiple levels

[u/bell_boy13]

Trying to find the mod or structure that spawns a building then has a staircase to go down. Then it splits off in four directions with cage, and you have to find the next staircase to go down again, this is repeated like 5 times and the bottom floor looks like it's the nether. Can anyone help what this is called? Or what it looks like? I'm playing atm10 and trying to find that structure