This is how you beat someone who outweighs you by 100 pounds: Stick and move at the tachiai. Keep the bigger man off your belt. Keep your hips low so when he pulls down on the back of your head you don’t topple over. Launch sideways out off the direct line of his attack. Launch back in with an attack of your own. Launch sideways again. Launch back in again, under his weight, keeping him upright and staggered. Control his hips. Keep him back on his heels. Stretch out as horizontal as you can so his right foot touches out before you fall. Go back home and eat a couple more bowls of rice so it’s not so much work next time.