The following review contains mild spoilers only.

In one of her increasingly rare moments of lucidity, Cortana â€" the sassy artificial intelligence who’s guided us through three iconic Halo games that have generated more than $3 billion in revenue for Microsoft â€" asks a favor: “If we get out of this, promise me you’ll figure out which one of us is the machine.”

Cortana is dying, an 8-year-old with a 7-year life expectancy. Her longtime partner, the Master Chief, makes her a different guarantee: We’ll fix you. Those aren’t empty words, either, coming from a man physically augmented and mentally conditioned from childhood to be humanity’s perfect soldier … possibly at the cost of his own humanity. Saving his last, best friend just represents the latest objective assigned to him. At first.

Unbreakable promises and questions about our very nature provide a strong foundation for Halo 4 (releasing November 6 for Xbox 360), the first in a new trilogy from largely untested developer 343 Industries. They also present an interesting metaphor. Expectations run high when you bring Halo into the conversation, and many people asked whether 343 could keep the magic alive without Bungie, the studio that created the Master Chief and made his war into Microsoft’s signature video-game franchise. Would the Chief survive the transfer from one creative team to another intact?

He did. Halo 4 keeps every promise it makes. The real question is whether you think it promised enough.

What you’ll like

Halo 4

Things change
A moment comes in Halo 4 when the Master Chief does something we’ve never, ever seen him do … something I never even thought he could do. The entire universe pivots in that instant.

We haven’t exactly gone without Halo anytime in the last decade, but it’s been five years since we last played as the Chief. It’s good to be home again. Even better, our pulpy space opera hangs on to the dramatic weight it found in Halo: Reach’s doomed last stand and makes the crisis personal. It hurts to see Cortana, one of the strongest women in gaming, so vulnerable and unsure, and her uncharacteristic glitches soon deteriorate into full-bore schizophrenic breaks. I actually hesitated a few times when the game prompted me to insert Cortana’s chip into, say, a weapons terminal.

But it’s entirely gratifying (and a little telling) to watch the Chief circle the wagons around her, back her to the hilt, and defend her against all comers even past the point where he probably should. This is new ground, and the choices they make push both characters in new, unexpected directions. That’s what I wanted. That’s what I got.

And we get to shoot things. The Master Chief’s tenuous plan to save his friend hits a snag when they’re pulled inside Requiem â€" a majestic, artificial world built by the ancient Forerunner race â€" along with a fanatical Covenant splinter group searching for a new god to worship. Turns out those zealots came to the right place. What the Chief and Cortana discover on Requiem puts mankind in the crosshairs of the Didact, an overwhelmingly powerful enemy with an eons-old grudge against our species. If you ever wanted to see the Master Chief completely helpless, the Didact will oblige you.

He also provides our new targets, and they are no joke. Prometheans come in three sizes (pack-animal Crawlers, hovering support unit Watchers, and heavily armed, heavily shielded Knights), but they operate as one interconnected unit. Forget jumping into a pack of them and shooting your way out. Prometheans defend, repair, and even spawn each other, so it’s crucial to apply some strategy in order to shut them down fast. I found popping Watchers from a distance usually made a reliable Step 1, but priorities change according to who’s killing you at the moment. Individually or in a squad, Prometheans make pleasingly dangerous adversaries.

Knights in particular are tough, tricky â€" they can teleport out of harm’s way if you start scoring on them â€" and imposing in ways Covenant forces just aren’t anymore, so it’s especially satisfying when you assassinate one. Game-wide, it’s roughly a 50-50 split between Prometheans and Covenant encounters, though it gets especially tense when both come at you at once.

So show up for the violence, stay for the story. Big things happen in this game. We see evidence of a resurgent humanity represented by the UNSC Infinity, a massive, fully-loaded dreadnaught also drawn inside Requiem. Hints drop about our race’s destined role as we march out among the stars. And watch the Master Chief’s body language closely. Something’s happening behind that expressionless visor.

Yes, the universe changes in Halo 4, and I’m eager to see where we go from here.

Halo 4

Looks good, feels better
Stepping up to your first vista of Requiem evokes a genuine sense of wonder and awe, not unlike the first time we walked out onto the surface of a Halo, aided in no small measure by the all-new graphics. Halo 4′s stunning visuals represent a quantum leap for the series and a serious bump on nearly any other game franchise you’d care to name. This game is endlessly beautiful.

That’s only the tip of the overhaul. 343 Industries took major cues from Call of Duty â€" current holder of Halo’s old first-person-shooter crown â€" to add a slightly more tactical edge to the familiar run-and-gun game, and everything feeds into that philosophy. It’s in the Prometheans’ rock-paper-scissors approach, the new grenade-warning indicator, the new armor abilities, and in how the best weapons in the Master Chief’s revised arsenal tend to be more precision-focused. The Chief even moves noticeably slower than before, balanced by a permanent sprint function. Man, does it feel different. But once you dial in, Halo 4 takes off.

For better and worse, I never dug into the short-burst Thruster Pack or enemy-scoping Promethean Vision (the range on both didn’t impress me). But a handy, deployable sentry turret and a mobile, hard-light shield became invaluable. I also clung to my scope-equipped Battle Rifle and the improved Designated Marksman Rifle (DMR) like never before. Seriously, I passed over energy swords to hang on to my iron. That’s unheard of in previous Halos.

But whatever you’re shooting, the audio design takes everything up a notch. No more mistaking assault rifles fired in the distance for misaligned typewriters. You bring thunder to a gunfight, and alien weapons truly sound alien.

343 retooled absolutely everything in the never-ending quest for balance. The Warthog jeep feels far less floaty; I actually enjoyed driving it. A lot of old favorites â€" Ghosts, energy swords, shotguns, jetpacks â€" feel slightly (and rightly) scaled back from their always-win status. New favorites abound. I grabbed any Sticky Grenade Launcher offered to me for the pure comedic value of remote-detonating my enemies. The Promethean Lightrifle (a super-cool Battle Rifle analogy) and sniperish, one-hit-kill Binary Rifle are definite keepers, though the SMG-style Suppressor seems too inaccurate. And I’d take a very scary squirt-gun over the Boltshot pistol any day.

On the other hand, picking up the ridiculously overpowered SAW, a BFG heavy rifle, pretty much puts you on par with God. That suited me fine in the campaign; less so in multiplayer.

Also overpowered is the heavily publicized Mantis combat mech. It comes in handy when a few squadrons of Banshees strafe you, but it doesn’t distinguish itself from any other recent gun-heavy mobile suits (Mass Effect 3, Gears of War 3, etc.). You hop in and fire barrages of missiles at one teeny little Grunt. Because you can. I actually preferred  getting behind the stick of a Pelican for the first time in the series’ history. That’s some long-deferred wish fulfillment … even if that sequence feels more like a reward for my patience than an actual challenge. I like rewards.

You get a lot of them in Halo 4. The rhythms differ, and the sexy looks are a surprise, but the gameplay feels at all times tight, precise, and joyous.

Particularly once you fire up the multiplayer.