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The Triumphant Declaration was a Covenant CCS-class battlecruiser that was present during and after the Battle of Mare Erythraeum on Mars in October or November 2552, as part of the Fleet of Furious Redemption.
Commanded by the Jiralhanae Shipmaster Lepidus, it held Colonel James Ackerson for interrogation following the battle. Ackerson's interrogation and subsequent torture led to him divulging the location of the fictional Key of Osanalan in Cleveland, resulting in the Battle of Cleveland. Following this battle, Ackerson revealed that the Key was a hoax, and Lepidus promptly beheaded him. 
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