Pointer: I remember reading about an island in the tropics where the rite of passage from boyhood to manhood was to skill a shark with a knife (no scuba, no nothing). I am not sure if I would have made manhood there
Maybe if everyone else does it, and you grow up with that... sounds pretty alien and scary though.
Ah yes, there was a tribe in Africa where the rite of manhood was to kill an adult Gorilla with a spear - this guy can literally tear you to pieces with his bare hands. The technique was you challenged him and pissed him off, and he chased you while you ran like hell with spear down the trail. At the last instant, you fall to the ground, jamming the butt of the spear in the dirt, and as he dives onto you, he is diving onto the spear. Also sounds, pretty... interesting.