Get Past the Death Barrier in Halo 3
1. Go into your game settings and make sure your health is set to invincible.
2. Choose the map of your likings.
3. Get outside of the map.
4. Spawn a machine gun turret on top of a couple of fusion coils or any type of explosive. (Be careful not too many)
5. Have the non-connection host dummy the turret. (Heres a Tutorial on Dummying)
6. Have the person who just dummied the turret get on it.
7. Now have a friend get in a tank (or just use a rocket launcher, hornet ect. Whatever you want) and shoot right below you.
If you did everything correctly you should be flying through the air. Have fun with this.