Exploration. The feeling that you landed on something very alien like, like the first time you stepped on Halo. Damn just thinking about that makes me want to play the campaign again. Too bad, Halo 4 didn't do that. You instead dropped into something very plain, all the way through orange and/or grey(except for that avatar. Oops I mean forest level), then you had all the help from Infinity. Is it just me or do the campaign levels seem linear? That QTE at the end was very anti-climatic. I hope that Bungie won't do anything stupid like that in Destiny.