"Snorkel test" to celebrate finishing my divemaster
A hip-flask of Thai whiskey, coke, and a couple of shots of whatever the instructors see fit. With a mask on you can not breathe, so you stamp your foot when you want your assistant to momentarily break the seal on the mask. I think this routine gets perpetuated as everyone who has done it wants to ensure the newbies are subjected to it as well. It was novel to get progressively more drunk over the course of a couple of hours, without having to drink!