(coexisting on another dimensional plane)
Odo was the officer in charge of running the ore processing center on Terok Nor in 2370. Odo had a strong desire for order and obedience, and ran the most efficient operation in the entire Klingon-Cardassian Alliance. He even created the Rules of Obedience.
Odo was killed by Julian Bashir, who had been forced to work in the processing center for the Alliance, during a thorium leak that disrupted the center's operations. In the subsequent evacuation, Bashir shot Odo with a phaser set to kill, destroying the Changeling. Intendant Kira Nerys lamented his death, as he apparently was the only one of his kind. (DS9: "Crossover")