I got farther in Halo 2 and wow, my mind is getting blown! So my brother and I are playing splitscreen co-op, and we get to this really lengthy cutscene where a "heretic" is taken to The Covenant Council for interrogation, and then they raise him up from "heretic" to The Arbiter, and The Arbiter and some other Covenant forces get ready to take down the true Heretic....
So we're thinking to each other "Wow this is really fucking cool, so I bet the game will soon be switching to a cutscene showing Miranda Keyes, Cortana, and Master Chief stumbling into this battle right?"
And then it turns out that we are playing as The Arbiter!!! We were so shocked, but we loved it.
And then at the end of that sequence of levels 343 Guilty Spark comes out of nowhere. Oh lord have mercy, my brother and I were just so fucking impressed. Right away we love the idea of how the Covenant are being fleshed out as more than just Other, Mindless Enemies. They're a fanatically religious civilization, extraordinary powerful, with unique individuals scattered among their ranks... and there is so much wonderful political intrigue. The Heretic is trying to show The Arbiter, via 343 Guilty Spark, that The Council is lying about Halo's true nature, but The Heretic never gets a chance. This was just beautiful.
And the feels/surprises didn't stop, because in the next cutscene, BAM, we finally return to the human storyline and Miranda Keyes, MC, and Cortana actually run into a NEW Halo!!!