I heard about a Red Ninja suit you can unlock. Probably around Halloween. I'm gonna so mess with the prefects' heads with that suit. Just imagine watching from a locker or trash can as a prefect gets kicked to crap, then wonders what happened. Or neutralizing a bunch of prefects with a stink bomb as they're chasing you, only to disappear once they stop chucking their lunch.
Good times, can't wait to get that suit.