Last year I beat him in the grand finals of a smash touney at a random anime convention in Ohio. When he lost, he immediately started screaming, grabbed a couple gamecube controllers within reach, fell to the floor, and started pounding them on the ground as hard as possible busting them down to circuit boards.
He was losing his mind, and three con staffers had to tackle him to keep him from lashing out at anyone else nearby. He curled up in a ball and they had to carry him out of the game room, where he stayed laying on the floor, sobbing in the hallway for hours. Hotel staff told him to leave, he wouldn't, and police ended up coming and zip-tied his hands and escorted him out.