Killzone 2. I would not be #1 but pretty damn high.
I've gotten "How the fuck do you get so much score?!" a few times.
I was one with the shotgun. No heads were safe around me.Yeah I would also consider KZ2 the game I was best at. No way near #1 in the world but I used to have some great scores. Especially as a sniper the ratio was awesome.