A substantial quantity of alleged Halo 4 details have started appearing online. The latest issue of Game Informer, of which 343 Industries ' next game is the cover story star, is hitting subscribers, some of which have been sharing details in various forums.

The story details Master Chief waking up four years after his cryo nap at the end of Halo 3. Cortana's detected an intruder on board, which happens to be Covenant invaders probably joining them from the fleet outside Chief's derelict ship. No word on why the Covenant are there at all, never mind why they've broken their truce with humans, nor what role they play in the narrative.The story that follows Chief's wake-up will, as we know , explore the humanity of John 117, as well as continue Halo 3's theme of Cortana as a rampant AI. In that four year break, Cortana's adopted a new look. As usual, the campaign allows for four-player co-op.

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In addition to new weapons to be revealed, the Covenant carbine and plasma pistol return alongside the human sniper, assault, and battle rifles. We'll also get to wield the magnum, rocket-launcher, shotgun, and assault carbine.The story carries over to Halo 4's multiplayer, which 343 is calling Infinity. This answers our question from earlier this week regarding Microsoft's newly registered HaloInfinity.net and HaloInfinityMultiplayer.com domains. Infinity has direct and indirect connections to the campaign, though details aren't present in the article.Frank O'Connor mentioned in the Halo 4 ViDoc that 343 came up with a valid reason for red to fight blue, and that comes in the form of military training on the combat deck, an adversarial simulator. This means we won't play as Elites online, as 343's focus lies on the Infinity's Spartan IVs.Adding to the Infinity experience is Spartan Ops, a separate story-centric campaign for four players. It presents objective-based missions and cinematics, both of which will be added weekly to expand on Spartan Ops' story. These updates will happen for months following Halo 4's release to hold players' attention long-term. Spartan Ops replaces Firefight, which won't have its own dedicated mode this time around.Another interesting change to Halo 4 is loadouts. Rather than everyone rolling out with the same weapons online, players bring customized gear into battle. Everyone packs a primary and secondary weapon, armor abilities (including active camo, jetpack, and hologram) grenade type (plasma grenade is still unconfirmed). Weapons still appear around the map, of course, but they appear in random spots via drop pods. In another interesting minor tweak, the respawn in Team Slayer is instantaneous rather than reliant on a clock.Oh, and since Chief vanished, Spartans have since learned to run; sprinting is an innate ability in everyone. Players can also use Forerunner Vision to peek through walls, Batman style. The X-ray vision upgrade is an armor ability you'll equip. Other abilities are unlockable via Spartan Points, the currency fueling the in-game economy. Points unlock additional Ops missions, armor abilities, and cosmetic upgrades.343 Industries doesn't seem to be pulling any punches in creating a Halo experience with a unique yet familiar identity. What do you make of the online changes and single-player story details?Need to know more? IGN's Halo 4 wiki has the answers.Source: Game Informer via NeoGAF

Mitch Dyer is an Associate Editor for IGN's Xbox 360 team. He's also quite Canadian. Read his ramblings onand follow him on IGN