The ninja can be tough. REALLY TOUGH. At the start, he'll have his sword. The way you have to fight him is to fight him hand to hand. It will take awhile if you aren't good with Snake's fighting skills. But when you gain control of Snake after the cut scene, just run up to him and punch him, if he jumps somewhere, just go to him and punch him again. Then he will tell you to fight as warriors, hand to hand, and bla bla bla. Ok, grab the ration at the bottom right of the map in the glass mini room, and grab the chaff grenades. Now when you fight him without the sword, wait for him to do his double twirl kick that he does. Sometimes he will pause to see where you are, just keep moving. After you see him do the second kick, run up to him and punch him. Sometimes he will jump in the air and do a slam to the ground, make sure you don't stand under that, it will take off a lot of life. But after he slams to the ground, run up to him and hit him. Keep doing this untill he jumps in the air and dissapears. Now he tells you to come and get him while he has his STEALTH CAMOFLAUGE on! This part is easy.......just put on your Thermal Goggles, or your Infrared Goggles, and look around for him in his hotspots. Trust me you'll find him. When he falls down on his knees, he'll start walking slow. NOW WATCH OUT FOR HIS PUNCH. When you try to punch him, he'll dissapear to the other side or the the side of you and he'll sting you with his big punch! Just go up to him and punch one punch and move in his direction and punch him with your little combo. Here is another way to do it, throw a chaff grenade and he will get stunned. He will only stay up for a little bit so run up and hit him. When you actually beat him, he will go into a blue orb. Don't go near it, it hurts you. Just pull out the gun and shoot him. It will take about 3-4 shots. And that is how you beat the Ninja or should I say...........