I would LOVE if this game had an endless dungeon. Floors would be "randomly" generated, and it would get increasingly more difficult as you go deeper. Maybe floor 18 could be vs jelly king (but no tokens dropped, or drop tokens, either way it's hypothetical). And then when you inspected someone it would list the deepest floor they had made it to on their inspect page.
I think this would be a lot of fun.
So, like a survival mode or an infinite Danger Room / Arena?
I'd play it. +1