Warthog jumping
From Halopedia, the Halo wiki
The Warthog Jump was first recorded by Randall Glass. It is commonly done in Silent Cartographer (Level), where you launch a Warthog into the air using grenades and/or rockets. In Halo 2, the Sputnik Skull can be used to make Warthogs fly farther than they would normally.
Directions
What Randall Glass Says
Randall Glass had a way to describe it.
Q: How did you get all of those grenades? A: You have to shoot some soldiers. Shoot 5 of your guys (dropping about 8 grenades total). They usually drop grenades when they die (0-2). Here's a hint, trigger a Checkpoint before you do anything (like shooting your guys). Revert to Saved if they drop nothing. Other people have discovered an easy method using CO-OP mode. You and your buddy carry 4 grenades at the beginning of the level. Melee each other from behind and you'll drop them.
NOTE: only dropped grenades will chain-react. The ones you find near the flipped warthog won't go off. Also, multiplayer grenades won't work either. Please try things before you ask.
