Even though "Halo: Reach" drops in just under 2 months, Bungie has been particularly crafty about hiding the game's features from the public eye. Every time you think they've shown all there is to show, they whack you over the head with yet another whopper.
Comic-Con's big "Halo" news is related to the Forge. First introduced in "Halo 3," the Forge allowed people to customize multiplayer maps, choosing weapon and vehicle placements, dropping down crates and creating new modes. While the options were pretty vast, there were obvious limitations. Apart from crates and exploding barrels, you couldn't add or change the scenery in any of the maps. That changes in "Halo: Reach."
Bungie have created an enormous map called Forge World which basically gives much more control to the player. It's a wide-open, varied expanse that's actually 5 maps in one, set in and around another map, the classic Blood Gulch canyon (now called "Hemorrhage"). Players can do a heck of a lot more with this space than they could in "Halo 3."
Scenery placement is now open to players, letting them drop down small, medium or large structures wherever they want. You can even leave objects floating in air or bury them in the ground, so the basic map geometry isn't going to limit you. Imagine the prospect of building a massive sky base multiplayer map from scratch. That potential is now in the hands of players. Very exciting stuff.
Bungie also revealed a handful of new modes, including Firefight Versus. Firefight was the co-op mode first introduced in ODST, which had players teaming up to take on waves of AI enemies. Same idea here, but unlike standard Firefight, you can now have players spawn in as individual Covenant soldiers, in the midst of a sea of AI-controlled ones. It's the closest thing "Halo" can get to playing as the zombies in "Left 4 Dead," and it adds an interesting twist on an already promising mode, especially for folks that don't enjoy standard adversarial battles.
Every time I see "Halo: Reach" I'm always sort of blown away by the amount of content they're stuffing into this game, and then, a week later, they'll announce some new, massive feature to make it even more expansive. With two more months to go, it really makes you wonder what more secrets Bungie has up their sleeve.