This gltich allows you to get behind the wall inside the building ner the end of the level halo and requires 2 people.
1. start a game at rally point alpha
2. go through until you get ot johnsons warthog
3. leave it there and go get the hidden mongoose and birng it back to the doorway
4. drive the mongoose in and put it here:
http://www.bungie.net/stats/halo3/scree ... d=36594934
5. then drive in the warthog and use the mongoose to ramp up to here:
http://www.bungie.net/stats/halo3/scree ... d=36595116
6. then have one player stand on the wortho, and the other jump from his head to here:
http://www.bungie.net/stats/halo3/scree ... d=36595300
7. then walk to the other side and explore the other side of the room!!
http://www.bungie.net/stats/halo3/scree ... d=36595434