I've watched live broadcast Sumo match once or twice, It's very entertaining.
はっけよい、のこった! (Hakkeyoi, Nokotta!) Was the sign from referee before and right when they're wrestling, Once two Sumo wrestler put both of his fists onto the ground, the match begin.
Sumo is more than just grabbing opponent's Mawashi (Loincloth belt)and throws opponent out of the ring, and unlike SF4, Sumo wrestler can't just simply smash each other with palms like E.Honda until opponent is K.O.
There's more than plain tactic for achieving victory, One of those various technique is the trick to lure opponent into offensive stance and counter with sway+palm pushing to make opponent losing their body balance and falls to the ground.
Anyway, Sumo is more than just a chubby people sports, It's really fun to watch.
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Luprand
It's a relief to hear someone else talk about sumo realistically.