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Regent's flagship at warp

The Regent's flagship

The Regent's flagship was a massive Klingon-designed warship that served as the Klingon-Cardassian Alliance's flagship for Regent Worf. In 2372, it led an assault fleet intended to recapture Terok Nor from the Terran Rebellion, but the ship sustained heavy damage in combat with the rebel warship Defiant and was forced to retreat. (DS9: "Shattered Mirror")

In 2375, the Regent's flagship was equipped with a cloaking device that was stolen from the IKS Rotarran of the mirror universe. However, the cloak was sabotaged by Rom during its installation, disabling the entire ship and leaving it vulnerable to attack by the Defiant. The Regent was forced to surrender as a prisoner of war in the engagement. (DS9: "The Emperor's New Cloak")