Halo 2 theatrical trailer
From Halopedia, the Halo wiki
Starting in Sept of 2002[1] there was a series of cinematic trailers for the Halo 2 Game. The ads were shown in movie theaters in the United States, available as downloads off the internet and shown on TV.
Halo 2 Announce Trailer
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The Halo 2 "Announce Trailer" gave a basic summary of the upcoming Halo 2 game and that namely the Covenant had arrived and attacked Earth. This video was recycled by Bungie for use in the Halo 2 cutscene Return to Sender
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Released in October 2004 the trailer starts out with the words: "The most lethal force in the universe". The screen flashes to a shot of several Elites. Then it continues: "Has destroyed everything in its path". It flashes a shot of a Pelican landing and a shot of a Ghost taking fire from a Phantom. It goes on to say: "On November 9th, What's in its path... is us." and the screen fades to a shot of the Earth. That shot vanishes. A Pelican roars over head. A ghost is chased by a Phantom. It shows the Master Chief standing on a roadway watching Orbital Insertion Pods descend on New Mombassa. The writing reappears and says: "We're not ready" and shows the Master Chief cocking a Battle Rifle, a Warthog engaging Shadows, and some shots of multiplayer. The writing then says: "He is". The camera changes and shows some wreckage. It pans up to show The Chief standing atop a chunk of debris, wielding a pair of SMGs. Several Phantoms fly over him. The Master Chief looks into the camera and jumps. The screen flashes to the Halo 2 logo with an orange clouded background. A voice then says: "Rated M for mature"