San shou, is a form of free style fighting.
It involves techniques such as punching, kicking and throwing and traditionally took place on a leitai (a raised platform,a bit like a boxing ring without the ropes around it). In the past the leitai was sometimes floated on water, so when a combatant was knocked out of the leitai they would land in water, making it more tiring for them and of course more slippery. In China, san shou competition would sometimes last over a number of days and several rounds fought.