I would say an invisible mime car but how would that even look or work. Then I thought, no it wouldn't be good enough. An invisible mime unicycle though, appropriately french and mime like thats the ticket. No idea what it would do. Quick thought is it functions similar to a segway but when the mime uses it they cannot be knocked off of it unless they run into a wall. They also get an invisible steel rod to joust the crew with while on it.
I also like suppressor suggestion by Mouse, gives a good rampage option.
I also like suppressor suggestion by Mouse, gives a good rampage option.