In Killzone 2 there are a few different ways to play. some play like Halo and some like Call of Duty I personally like the Call of Duty because you can look down the sight of the gun and its more fluid for gameplay. In the single player campaign there is a cover system that works quite well for a FPS. but it is removed in the online part so its more fast paced. The melee system is not an instant kill but 3 successive melee's to a undamaged enemy is needed to kill them the melee's are much quicker than Halo so 3 is Killzone is 1 in Halo.
The campaign in KIllzone 2 is an interesting one, its not the basic Black and White good and evil, half of the time i wanted to join the helghast and not kill them, there leader Scolar Visari had some of the best speeches in games i have ever played. I know its not the best story but its a realistic one about politics and no extinction from aliens or zombies. its a average sized campaign but a great thing is the AI it will learn what your do so it can counter you. its the best AI ever created in a video game
Ok every gamer knows that Halo is the king of FPS online and CoD is second, but Killzone 2 has an addictive and interesting online component. it revolves around a badge system were you can be a solider, a medic, a engineer, a tactician, and assault, a saboteur, or a scout. all of these classes have a primary ability, but when u get enough ribbons your can interchange secondary ability's to customize your character. With the ability to change the game mode during the match will make it fluid to kill people capture a area or play capture the flag with a propaganda speaker