Crystal tower and parties challenge- why not?

[Felis]

Dont tell me, that you want to be inside of the dungeon for hours. You want to clear it quick as anyone else.

I dont speak about speed runs, but about making dungeon more fun

No problem.
Just do it that it get faster the more the people work together instead against each other.
The moment someone work against the alliance it should be a wipe. This would be real challenge.