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Presumably February 13, 2526
Battle of Bliss
Bliss Defense Fleet
UNSC Matador was a UNSC heavy cruiser.
On February 13, 2526, Matador fought at the colony of Bliss alongside the cruiser UNSC Weeping Willows and the frigate UNSC Purpose against a fleet of 45 Covenant warships. The UNSC battlegroup was presumably defeated, as Bliss was glassed soon after the engagement.