Any gamer with even an inkling of interest in Halo 3 should head over to Gamersyde right away and check out some of that site’s stunning off-screen campaign footage, a sample of which we have posted above.  This video shows off the game’s unique replay feature, which allows you to record and play back entire levels of the single player campaign, as well as multiplayer matches, at your leisure.  Players can then use the footage to analyze their enemy’s defenses, exploit weaknesses, and polish their own skills to a Legendary sheen.  Note how the Bungie representative in the video uses the feature to check up on the exploits of a group of Marines on the other side of the battlefield!  This is awe-inspiring stuff.

Halo 3 hits the Xbox 360 on September 25th, but of course you already knew that.