I feel like this would be a good idea. There has never been very much told of what is below the surface of Cradle. On the various surface levels we have had, we know for sure that the underworld layers are filled with mechanical constructions of some sort. Perhaps that's where the bulk of the monsters come from? I've always wondered ever since the Gremlins first showed up in the Lab.

Although I won't ask for much, I feel like there is a lot that could and should be worked with to really make the underground levels stand out among the usual surface levels. Perhaps we could have various terrains and monsters filling each one, or give it some sort of randomly chosen path to make it a bit more unique for every run. I think OOO could also add in a few new bosses unique only to the lowest levels. Perhaps they can even have a secret "core" location at the very middle of the planet. That would be cool!

I like this idea. I think it would bring back a lot of players. It also paves the way to an epic final battle against the devil himself! We can make that even better by setting the location in a harsh office environment with enraged overtime OOO employees!