The mirror universe's copy of the Defiant, built by the Terran Rebellion from stolen plans and made battle-ready with the unwilling help of Benjamin Sisko in 2372.
The ISS Defiant is the Terran Rebellion's warship in the mirror universe. After Miles O'Brien, known as Smiley, copies technical data from Deep Space 9, the rebels build their own version of the ship at the captured station Terok Nor.
In Shattered Mirror, set in 2372, the rebels cannot make it work in time to meet an Alliance fleet led by Regent Worf. Jennifer Sisko lures Jake across so that his father will follow, and Benjamin Sisko agrees to finish the ship. He then commands it in the battle, where it cripples the Regent's flagship and forces a retreat.
The ship returns in The Emperor's New Cloak, attacking the Regent's vessel once Rom has sabotaged its new cloaking device.