How do you play TWO players ON xbox black ops?

It can't be done on LIVE or split screen, why? Cus when you play GG you advance guns when you kill someone so it would pretty easy to kill somebody on split screen cus you could just look at were the guy is, plus in LIVE its would be really boring with two people i mean whats so much fun playing in Array with two people not even Nuketown would be fun. But me and my step Bro have ballistic knife wars there were you use tomahawks ballistic knifes claymores and killstreaks all in nuketown. Its really fun try it!