In the mirror universe, Si Cwan was the Prince of the Thallonian Empire and older brother of Kalinda Si Cwan. He was the captain of the Thallonian flagship, the Stinger, which at its core, was powered by the god-like abilities of Mark McHenry. When Cwan returned to the Stinger, he privately discussed with Kebron about his meeting with the Praetor. They both came to the conclusion that he was both paranoid and delusional, though Cwan made it clear that they were doing this mission in order to strengthen their bond with him for their plan to kill him.