The dominant theory about Bungie's next game is that it will deal with events from Bungie's previous trilogy, Marathon. What is this based on? Well, a number of items, the most significant of which I believe is first (Caution, below are some potential spoilers for Contact Harvest. They're not major story spoilers, but they are small 'surprises' within the story.):
- Game Informer says so. Wait. What's this? Since when do they own the Bungie rumor mill? Well, since they landed the Halo: Forerunner story several months before Bungie officially announced Halo 3 in early 2006. In the article, they talked about Bungie's next game being centered around the Master Chief, showing off scale, having large encounters with a variety of choices, heavily fleshing out details about the Forerunner history and including 4-player online cooperative play - none of which could have been known without a source on the inside (the latter, no one expected until the beta hexcode snafu), at least not that early. Likewise, just a month or so ago, the magazine ran another rumor blurt claiming that Spartan-117 and the protagonist in the Marathon series are the same individual, meaning that 'Halo 4' will take place several hundred years after Halo 3's events and involve the ex-Spartan/Master Chief character as well as the general storyline utilized during the Marathon game.
- What about the Edge 'shooter' comment? January of this year, during an interview with Edge, Harold Ryan, Bungie's Studio Manager, let it slip that the next 'Halo' game will likely be a shooter. [Edge, Partly, but not entirely. With likely less than a year of Halo 3 development left, and the end of this monumental trilogy (though not necessarily of Bungie Halo games – Ryan at one point refers to “the next Halo game" and says it will likely be a shooter) in sight, the germination of new, original projects is already underway.] Marathon is obviously a shooter, for those even with a cursory familiarity of the trilogy.
- And the obvious Legendary cliffhanger. The end of Halo 3 places the Chief and Cortana, not simply at the finality of the Halo Trilogy, but seemingly at the start of a new adventure, as the broken frigate section floats past a large structure described as a 'planetoid' by Joe Staten. [GameTap, There is a crazy planetoid floating out there. Who knows? If you look really, really carefully at the lights on the planet, though, there is something to be seen in those lights.]
- The Planetoid's secret billboard... Others in our own group (NJ, here's looking at you) have suggested that the item being described on the 'planetoid' installation is, in fact the Marathon logo. There are similarities, although nothing confirmed.
- Contact Marathon. The Marathon logo has been confirmed, within Halo canon, that it is more than simply lip service to the studio's previous IP within Halo's easter egg cache. According to Contact Harvest, it's the symbol for 'Reclaimer,' a crucial part of the Halo mythology. [Halo: Contact Harvest pg. 274-5, < THIS IS NOT RECLAMATION > the Oracle boomed. < THIS IS RECLAIMER > Slowly the glyph turned upside down, and its central shapes - the concentric circles, one low inside and the other, connected by a thin line - took on a different aspect. The shapes' previous arrangement had resembled the pendulum of a clock. Inverted, the glyph now looked like a creature with two curved arms locked above its head.] Not only does this tie the Halo and the Marathon universes together, but it also bridges the gap between the Master Chief and the main protagonist of Marathon.
- Terminally positioned. The terminals in Halo 3 clearly show that some of the Forerunners partook in 'The Great Journey' during or immediately after the Array was launched and perhaps it was their goal that their human 'descendants' to follow their footsteps. If by firing the replacement for Installation 04, the Chief and Cortana were carried on that Great Journey, this could be the linchpin in restarting in a Marathon setting, tying the Forerunners to Marathon's Jjaro, as well as some of the other very obvious parallels.
Now, keep in mind that I'm not suggesting that Bungie is about to remake, word for word, every square inch, the Marathon series, but it does seem likely based on a number of factors that Bungie will revisit the franchise by remaking and re-envisioning the series in the light of the events of Halo 3, particularly those events which stand out at the end of the Legendary cinematic. I remember in a video tour of Bungie's studio, Frank jokingly scoffed about their 'next project' being Marathon IV, by having it scrawled on a white board and then erased for humorous effect (11:19 minutes), but ironically (and much to my chagrin), the end of Halo 3 and these other factors set the player up perfectly for some type of return to the Halo universe, and a return as the Master Chief.
I've openly stated that I don't like the idea of them using the Master Chief again and that they would have to make one hell of a sell for me to not see it as a cannibalization of a perfectly finalized IP, but if they sell it through Marathon it might work actually work - then again, I still have some serious reservations considering the conclusion of Halo 3.
But wait, you say, Marathon's first game is set in 2794, right? That's 242 years off of Halo 3's ending in March of 2553, so the Chief who is approximately 43 years old in the trilogy would be 285 years old by the beginning of the the Marathon series. That is technically true from our non-fictional standpoint. Of course, Halo: Contact Harvest says specifically that in the Halo universe you don't age during cryo-sleep at all [Halo: Contact Harvest pg. 64]. In fact, the idea that the Master Chief is even 43 years old is questionable. He may well be in his early 30's, as even Sgt. Avery Johnson questioned that he spent half of his life in cryo-sleep, which made keeping track of his biological age a decidedly difficult endeavor.
So, from my perspective at least, the pieces are set in place to revisit the Marathon series. For those who have yet to know what the series involved, it was basically two games, Marathon and Marathon 2: Durandal, with a third, Marathon Trinity, replaying some events of the second game with added sections and features. The game, like the Halo trilogy, is a gun-heavy, shooter based in a science fiction world, set almost entirely in space and by in large against an alien race (in Marathon, they are called the Pfhor and like the Covenant, they are a class-based, multifaceted enemy). Weapons in Marathon are considerably similar to those in Halo, and iconic elements like the 'UNSC' exist simultaneously in both series.
Here's the Wiki for those looking to go the extra mile.
So, what do you think?