he is bigger, faster, stronger, has a black belt in three different types of martial arts. He can throw a punch with almost 500 pounds of force, am i screwed?
Scoop him up and bring him to the ground. There is an old saying everyone is the same size on the ground. Besides he will probably be expecting you to try to kick him in the nuts. So this may throw him off alittle. But if he is what you say he is you will need to strike with lightning speed. It's not impossible. You can do it.
why would you want to pick a fight with that kind of guy for? Seems pretty stupid to me. Get your measurements taken, you'll need them for your coffin.