I personally love the story, I think it's one of the best I've ever seen and played in a video game. Not only that but the multiplayer is great, I played KZ2 a little bit but I've played KZ3 a lot more and I just have a blast whenever I play.
Why do you like the Killzone series?
I like the online part, but yes the story mode is good. Not so happy with KILLZONE 3 online. KILLZONE 2 online was really a lot of fun and if Guerrilla make a new Killzone hope the online go back to KILLZONE 2.