What no Rambling Bumbler can resist

What’s the worst that could happen?

My players are congenitally unable to resist this kind of thing.  After one campaign where they destroyed the universe by shooting the doomsday machine before the villain could finish explaining that shooting it would doom them all, I’ve taken the precaution of removing all self-destruct mechanisms and other single points of failure from every subsequent setting.  And they still go searching for them…