Hm, I can only talk for myself why I like KZ2...so here we go:
-great atmosphere due to the gritty look
-tech is ultra impressive, still one of my favorite games with respect to graphics (especially: all the particles, smoke and debris after 5 seconds of firefight...making the immersion rather intense)
-I like the cinematic views in cutscenes
-Enemies are demanding
-Animation for me are the best available, especially bullet hit reaction + death animation
-Sound is one of the best IMO...if you have the right setup available of course
-First Action game, where I like the vehicle missions (which is basically due to the fact that you play as a Mech with rather similar controll...in this section, explosion+overall are so chaotic that you simple have to love this stuff, IMO of course)
-graphic fidelity/design increase during SP campaign...I was shocked when I first entered the train mission for instance, still unbelievable to me today (try the MP map): lightning, postprocessing, physics...nearly perfect and made me wow all the time (even convinced one of my best buddies who is a die hard PS3 hater!!)
-gameplay felt unique (due to whatever reason
)
-some memorable set/action pieces
-Radek is an ass
-no dumb "USA protects the world" story
-Online MP was fun, exploring new classes with new abilities...of course until you have unlocked everything!
-one of the rare SP campaigns which I actually played more than 1 time ... still frequently checking out the salamun bridge sections!
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