Jumpmine
From Halopedia, the Halo wiki
The Brute land mine is an explosive device used on the Halo 3 map Sandtrap to keep the player inside the map. When a player gets to close into it's proximity, it will be launched up into the air and explode out in about a 15 meter radius. It does not kill the player in one hit but surly in two hits. Physical appearance is similar to a Spike Grenade without a handle.