Once the fight starts, run over to Vamp and get as close as possible to him without falling into the water. Immediately equip the stinger missile launcher and begin to constantly bombard him with missiles. Tap the button as fast as possible to defeat him in about fifteen seconds.
Under the extreme difficulty setting, at the start of the battle when Vamp bows, shoot him with the Stinger. You may do this two or three times if you are lucky. As soon as he goes underwater, shoot the lights out quickly before he comes back up. When he first goes underwater, he will come back up after about one sixth of his oxygen is used, unless of course you shoot him while he is underwater (which will deplete his oxygen after a few shots). If you shoot the lights, you will most likely not have enough time to shoot him while he is underwater. During the battle, Vamp will alternate between standing above you while throwing knives at you, and chasing you around on the catwalk trying to slash at you. He always starts the battle by going above you while throwing knives. When Vamp throws knives while above you, wait until he starts throwing them in rapid succession. When he does this, try to anticipate his movements so you will end up directly beneath him once he finishes throwing the knives. As soon as he stops, fire repeatedly with the Stinger. You can hit him about three or four times. When he goes underwater after throwing knives at you from above, place a Claymore mine on the catwalk to the right as you enter the room. Then, stand on the southernmost catwalk in the room as you enter. Stand to the right of the line that is in the middle. When Vamp comes up, he will run directly into the Claymore, causing him to go back under. When Vamp's life bar reaches about one third, he will change his knife throwing pattern. He will throw two knives in rapid succession, then pause for a second or two before throwing a third knife. He will do this three times before going underwater. With this knife throwing pattern, it will be tougher to hit him. You may want to dodge his knives rather than try to attack him during this time. If you do decide to attack him, do so by getting your Stinger ready before he comes up. When he comes up, shoot him immediately when he lands. This can be dangerous because you will be open to attack from his knifethrow if you do not hit him. if you do not attack him, a good strategy to avoid getting hit is to run in circles while moving in a zigzag pattern. Also, do not let him get close to you with your back to him. If this happens, you are very likely to be hit. Once Vamp's life is down to approximately one tenth, he will change his attack pattern. He will move around very quickly and occasionally throw five or six knives simultaneously. The best way to hit him during this stage is to track him with the Stinger and fire just as he is about to throw knives at you (or any other time when you think you can hit him). This final stage is the toughest; you will have to be very quick not to get hit. Try to make sure you have full rations for this battle (especially the last part).
When the battle begins, shoot Vamp. When he goes into the water, run anywhere near an edge and plant a C4 bomb. After that, jump over the edge directly next to the bomb. When Vamp approaches, he realizes that he cannot hit you and jumps down. He will start to walk toward you, and when he steps over the C4, blow him up. He will jump back in the water. Repeat the cycle until he dies. Note: Act quickly, because if he jumps up before you are done, you will be knifed.
To make the fight against Vamp easier, simply shoot out the four lights positioned around the room. Vamp will no longer be able to freeze your shadow, as you no longer have one.
Run directly up to Vamp and throw a couple punches and kicks. After three or four punch/kick combos he will be knocked out.