And still - somehow - there's more. With the new Forge tool, players can tinker with the game's maps (including the locations of weapons, vehicles, architecture, respawn points and more) until they're almost unrecognizable. Tweak the game's rules using the same menus and you might invent Halo Baseball, Halo Kart or Halo Counterstrike. Or, if careful building's not your thing, an equal amount of fun can be had simply experimenting and goofing off with friends.

Likewise, the Saved Films engine is not meant solely for would-be machinima directors. The freedom to detach yourself from a straightforward replay and guide the camera anywhere - no, seriously, anywhere - is a wonder to behold both visually and technologically. Unsatisfied with Halo 3's graphics? You won't be once you've circled 360 degrees around a plasma explosion or zoomed within inches of the bullet that's about to bury itself in your opponent. Plus, searching through Saved Films of your past campaign heroics can actually make hunting for hidden Skulls enjoyable.

Four-player cooperative mode also rocks, transforming the solitary story missions into wild online parties full of score keeping, trash talking and nonstop vehicular mayhem. Beat the campaign by yourself to absorb the cut scenes, but do not miss out on the team experience afterwards. You'll discover strategies that only work with a group, vehicles that only dominate with three friends riding shotgun and secrets that only reveal themselves when four pairs of eyes are looking for them. Besides, how else will you finish on Legendary?