In this tutorial, we learn how to do the Mas Oyama secret technique. This uses manipulation of the muscle. You will face your opponent and hit them in the gut with your hand. Keep your hand straight and have your thumb bent, so when they move forward and you hit them, your thumb goes straight into their stomach. This will make them fall down to the ground and lose control over what they were just doing. This is a very painful technique and there are no secrets or other techniques to do this. Be careful when doing this, then good luck with your fighting!