Using right technique in the right time means a lot in BJJ. And in this situation we can see exactly that.
In this video we can see an outsized purple belt with only 143 lbs submitting a BJJ Black Belt who weights 300 lbs. It was a real struggle for this Purple belt but he managed to do it. Check out the video below.
You can also check a match between outsized BJJ Blue Belt vs Hapkido 6th degree Black Belt in a grappling match.
Check video how small gay takes down a big bully.