I think it is known in Japan as Brain Wall or something like that, but most call it Human Tetris.
Basically, it's about a person from one team trying to ready himself in a correct position as a wall comes towards him. The wall has a certain shape that the person must go through. The objective is to not be pushed into the water behind him from the wall coming forward. If he passes through the shape, the team gets points.
Has anyone seen it before?
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