Halo 4 is probably the most interesting thing that's happened to the Xbox's most crucial first-party series in ages. I mean that from a faraway, academic point of view, though. It's the first time in the franchise's long lifespan that anyone other than Bungie has taken a stab at creating a core Halo first-person shooter. Will it play like Halo? Will it feel like Halo? Is there any more room for fresh storytelling in a decade-old franchise that already wrapped up its initial trilogy with a nice tidy bow? Those were the questions that swirled in my head as Drew and I flew up to 343 Industries in Washington last week to get our hands on just about every aspect of the game Microsoft's flagship studio has been slaving over.Campaign. It's what I personally care the most about in Halo 4, and it's what 343 has shown the least of since that banner gameplay demo kicked off the Xbox press conference back at E3. So let's talk about it (unless you're sensitive to very light, first-couple-of-mission-type spoilers--but if that's you, why are you even reading a Halo 4 preview?). What we got to play was mission one and mission three of the Halo 4 campaign. There's a prologue at the very beginning the contents of which I know not, and then 343 said some momentous stuff also happens in mission two. So I don't have the whole picture yet, but I've started to form a concrete idea of what Halo 4 is actually going to be about, and how the story bridges the gap from the natural conclusion of the last game.Maybe my expectations for the starting premise of this game were a little overblown, but there's really no great mystery to it. Master Chief and Cortana were adrift at the end of Halo 3, with Chief entering cryo-sleep against a promise to Cortana that he'd wake up when needed. Five years later, with rogue Convenant forces boarding the ship for unknown reasons, he's definitely needed, so you pop right out of that cryo pod and get down to the business of mowing down grunts, jackals, and even elites (!) as you make your way through what's left of the UNSC Forward Unto Dawn. While the greater organized Covenant was handily dealt with at the end of Halo 3, this splinter faction doesn't seem too worse for wear; they've surrounded the Dawn with half a dozen capital ships, and getting Chief and Cortana the hell out of there is your immediate priority, nevermind the giant Forerunner vortex that's rapidly sucking all these ships in...Playing Halo 4 in that first level is like pulling on an old pair of gloves pretty much from the second you pop out of the pod, and maybe that's not surprising since Halo steward Frank O'Connor told me that Bungie's existing codebase served as a starting point for every aspect of this new game. The basic movement and shooting are pretty much exactly like you remember, to the point that I immediately went into settings and adjusted my look sensitivity the way I remembered liking it. I also played that first level on Heroic to get a better sense of how faithful Halo 4 is to the "combat puzzle" that's so central to the series. Most of that first level is a lot of tight corridor-crawling where you're only taking on a few enemies at a time--punctuated by a couple of scripted first-person action sequences that felt out of place, if not unwelcome, in a Halo game. But the end culminates in a wide-area low-grav battle in the part of the Dawn exposed to space. Out there with enemies coming at me from all sides and a couple of jackals sniping me from up on a ledge, I died several times, and each time it felt like the battle played out noticeably differently as I tried different positioning and going for different weapons. It was a relief getting that big battle in at the end of the level, since that kind of fresh replayability is exactly what I'm looking for in the Halo combat experience.As familiar as the game feels in that first level, though, the little things here and there that aren't the same really stick out like a sore thumb. Why does the assault rifle sound like a different gun? That one really threw me off.It's in the third mission, "Forerunner," where things really get interesting. Having missed the previous level, I don't know how Master Chief and Cortana got from that vortex into a dark, rocky canyon area full of Forerunner technology and architecture. But you don't have much time to think about it, because you almost immediately start fighting the new Promethean enemies 343 has devised as an entire new faction for Halo 4. These guys obviously behave completely differently than the Covenant and create some different combat dynamics as a result. The knight seems to be the Promethean heavy, the way he strides around with a giant energy sword and can leap at you from far away to beat the crap out of you. He's hardly invincible though, as I found one point-blank shotgun blast was often enough to end a knight, assuming one of the flying watchers wasn't hovering nearby. I made a point of going after the watchers first in every new encounter since they can generate shields around ground-based Promethean enemies, as well as grab and return your thrown grenades. The four-legged crawler can also cause a lot of problem, since they tended to show up in packs and can swarm you pretty readily. Oh yeah, they can shoot at you from a distance too. The Covenant and Prometheans aren't fans of one another, so I found myself in more than one three-way battle with everyone shooting everyone else in that third level.Halo 4 will have a pile of new weapons, of course, like the Covenant storm rifle, an energy-based popgun that I didn't find especially powerful or fun to use. (All the old hardware is still there and still perfectly useful, of course. Drew thinks the needler is especially potent this time around.) But it's the Promethean arsenal that's most exciting, since it's a whole new class of weaponry the likes of which we've never seen before. Visually, the orange-trimmed Promethean weapons look amazing, the way they defy gravity and form together out of component parts right in Master Chief's hands. Functionally, the five weapons in the level I played fell into familiar categories, though with a twist or two here and there. The boltshot acts as a basic but powerful pistol, unless you hold down fire, when it will build up charge and automatically fire a burst more akin to buckshot. The scattershot actually is a shotgun-type weapon, and it seems like its shot might ricochet off of walls a bit. The light rifle seemed like the backbone of the Promethean arsenal, with its rapid fire and light zoom. There's another automatic weapon called the suppressor which is more like a submachine gun; it felt uselessly inaccurate at more than a couple dozen feet away. Lastly, the binary rifle, which I only picked up so close to the end of the level and didn't get a chance to use. As the name implies, though, it's an on-off weapon. If you hit with it, you get a kill; if you don't, you don't.In the midst of all the new enemies and weapons, some familiar scenes played out here and there. There were multiple vehicle sequences in this level alone, first letting me plow through an open battlefield on a ghost, then later giving me a banshee to fly around and wreak havoc with. The third mission was capped off with another ghost sequence that had me hauling ass out of that desolate area as the walls were all crumbling around me. It wasn't entirely dissimilar to the ending race sequence of the first Halo.There are some things I'd love to know more about after playing these two levels. What the hell is the nature of the Prometheans? Are they robots? Is there anything alive in there? What's with that weird skull? Cortana also makes references in the third level to her encroaching rampancy, the Halo-universe idea that artificial intelligences don't stay sane forever and eventually become super-smart beings of malevolent, all-powerful contempt for everything around them. That sounds like a bad state for a computer program that lives in your head, so finding out how Master Chief plans to deal with this particular story thread should be interesting.Some significant plot stuff happens at the end of that third mission that makes me think I know exactly what the broad premise of Halo 4 is going to be, but since Microsoft asked us not to talk about it and really just let us see it for context (with missing music and sound effects, no less), there's not much point in worrying about whether I'm right or not. I will say it creates a particular narrative dynamic that Halo hasn't really dabbled with before, and that's exciting. The cutscene in the next level picks up right where that E3 demo began, and for whatever reason, it felt comforting to see Master Chief running around those rolling green hills that have provided the backdrop for so much of the series so far.Thinking about the feeling of comfort that a simple familiar environment brings about, I realize I'm in a weird spot with Halo 4's story mode. For a big-budget shooter that sells millions of copies, Halo always struck me as a series with an oddly high degree of quirk, from the manic, childish screaming of the grunts to the UNSC's bizarre ship-naming conventions to the fact that so many of your weapons are purple. There's a lot about Halo that's just weird. While some of that personality will transitively carry over to Halo 4, it also feels a bit more serious and grounded than past games. You know, the new enemies are less droll and more just grimly intent on murdering you. The lovably janky old cutscene animation has given way to modern performance-captured characters (that admittedly look fantastic). Infinity isn't an especially weird name for a ship. Everything I saw of Halo 4's campaign looked great, so I have to tell myself these reservations are merely the result of that pesky knee-jerk fear of things that are new and different. "You didn't want them to coast, right? You wanted them to do something original, didn't you? So suck it up and give it a chance." And so I shall.We also got to run through two of the five missions from the first episode of Spartan Ops, the 10-week co-op series that will be rolling out as DLC after Halo 4 hits stores. As I expected, the story elements within these missions aren't particularly strong and mostly consist of some voiceovers from your commanding officer (though there may be some external cinematics in this mode I didn't see). But the missions themselves seem to be picking up the slack by offering some pretty diverse combat scenarios. The first one, Land Grab, took place in a wide-open desert area with multiple warthogs and wraiths around, and had us in two-man teams fighting waves of Covenant coming in on dropships. The second mission, Sniper Alley, had us navigating a complex series of walkways and fighting enemies largely at great range, though at the end we had to hold off waves of enemies on the ground while we planted some explosives. At a dazzling 50 missions, Spartan Ops seems like it will offer a staggering amount of co-op combat for anyone who wants to keep playing Halo 4 for more than two months after release. Again, though, it's the campaign that's got me most interested here, and I've seen enough, and been impressed by enough, to be eagerly ready to get my hands on the final version.