Type 14 Magnetic/Anti-Tank Mine
From Halopedia, the Halo wiki
The Type 14 Magnetic/Anti-Tank Mine is a piece of UNSC explosive ordnance.
The Type 14 Magnetic/Anti-Tank Mine is used as both a mine and a satchel-charge type of bomb, containing 6.8 kilograms of C-7 foaming explosive. The arming fuse can be set for five, ten, or fifteen seconds. The magnetic attachment device ensures that it will adhere to a vehicle that passes over it.
It is used exclusively in Assault-type games from Halo 2, Halo 3 and Halo: Reach multiplayer matches. In Halo: Reach Invasion gametypes, players playing as Covenant Sangheili utilize a Riruku-pattern void maker for similar purposes.
In Assault games with standard settings, the bomb will have an unusually high melee strength, to compensate for the bomb carrier not being able to use their weapons. The bomb is usually a one-hit-kill from any angle.
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