Ok so from what I have herd around from other people at various clan sites and such when he goes into a tube thing its a health pod and helps him. Now your suppose to grab mines if you havent already and throw them into on if not all just make sure you have enough to kill him. When he goes to the pod that you have your mines in then blow him up and he should die. I didnt grab if its only once you have to do this or twice. I'm about to try and I hope this helps. Along with if you are a NOVA online player please visit http://www.iclans.tk for clan new for mc2 and nova2 there are a bit of clans there looking for recruiting. This has been Op7iX_ReD_FawX and I hope this has helped.
OK i can personally say that this works. I tested it just now and beat the game on medium difficulty. "Can't imagine what it will be like on hard" Anyways it takes about 4 mines. What I did was randomly choose one and play while the pillar supports "green things" are still there and used them to take cover while pilling about 4 mines in one of the regeneration pods. Then took out a rocket and weakened him till he went in one. If the one was not the one I choose then i kept trying but usually gave up till and restarted till he went in my pod and used the supports as an advantage! I'm soo happy I finally beat it! lol been driving me crazy for days.
Yes, all you have to do is run around, avoiding the centaurs rockets. (tip, if you have full health, his machine gun shots won't kill you, but they will get your health low -to red-) After he has shot his certain amount of rockets, turn around, and throw 4 gernades into the chamber. Don't worry when your health gets low, you won't die. When he is about to shoot his rockets, I heard him make a strange noise. When he makes that noise, quick turn around and run from side to side, dodging his shots. Run over too the pillars, gain full health, and repeat the process on the other side(make sure you have enough mines to start.) After all the mines are placed, use the pillars for defense. Shoot him with strong weapons. When he goes into his chamber, quick switch weapons to the detonater, and blow him to pieces. Hope that helps!