Fleet Admiral Terrence Hood
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Summary
Fleet Admiral Terrence Hood, nicknamed "Lord Hood" by Sergeant Johnson, has a very high rank in the UNSC. In Halo: First Strike, he was part of an ONI council that included Major General Nicolas Strauss and Colonel James Ackerson. In Halo 2, he outranked Fleet Admiral Harper, thus enablind him to recall the fleet to defend the MAC Guns.
In Halo 2, on board Cairo Station, he gave Sergeant Johnson the Colonial Cross for "acts of singular daring and devotion", as well as giving Miranda Keyes a posthumous award for her father's actions during the Master Chief's adventures on Installation 04.
He was the one that erroneously stated "the fleet at Reach was fifty times this size", although this is most likely just a rough, passing comment about how small Regret's fleet was (15 capital ships) in comparison to the Covenant fleet at Reach which numbered approximately 314 capital ships.
After Outskirts, he is not seen or heard from again until the final cutscene of The Great Journey, where he and a few remaining personnel of the Cairo station are still fighting off the invading Covenant ships.