From Halopedia, the Halo wiki
The Hades Corps was a branch of the UNSC Marine Corps of Engineers specializing in demolition. Between 2548 and 2552, members of the Hades Corps led by Sergeant "Ghost" were assigned to destroy a prototype suit during the Battle of Algolis to stop it falling into the Covenant's hands. As time was running out with shuttles lifting off-world and many of his men still stuck on Algolis with the Covenant closing in, Sergeant "Ghost" activated the detonation sequence of the suit to buy enough time for his men in the Hades Corps to evacuate off the planet and then destroyed the suit, completing their mission.
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