Halo 3  

my boyfriend loves halo, halo 2, and halo 3. he's been playing since halo, and he has become very addicted. that is the game he plays before he goes to bed at night and when he wakes up in the morning. i ve watched him play it and he is really good, he is a 32 but that is becuase he has started his account over on account of him getting matched up with people who arent good and his stats going down. but his favorite thing is to snipe. he has gotten triple kills, killing sprees, all kinds of awards. me personally i dont see how one game can make you want to play for almost 8 hours straight.i think to be good at it you just have to be smart and have good aim. you have to be quick on your feet.and you have to pay attention.

Well, since halo 3 is just halo 2 with a few new maps and a "man-cannon" and I had halo 2 I'd say its your kill to death ratio. If you die 50 times but get 49 kills in a 50 point game you still lose. Also, if you never die, but get no kills its like your team is playing with a man down. But if you can get like 10 kills with only a death or two your team benefits the most because your kills add up but the there team needs to kill your other allys more since you rarely die.

well how i am good is u gotta use stragity
help your partners
use the radar
watch your back
and always have a long and short range weapon
EX
battle rifle and shotgun

Being good at halo is a mix of all. You need to be good with the weapons to get the kills but if you are mentally better than your enemy you can kill him easier with less effort if you outsmart them.