Captain Cold
In the alternate timeline of the "Flashpoint" event, Evan McCulloch is imprisoned in the mirrors in a place called the Mirrorverse. It is mostly assumed Captain Cold killed him, and he cannot leave the Mirrorverse or he will die. Anyone else entering the Mirrorverse will die also. Mirror Master assembles the Rogues members Weather Wizard, Tar Pit, and Fallout. Mirror Master then escapes from Iron Heights and pursues revenge against Captain Cold for imprisoning him. Captain Cold kills the Rogues members and then enters Mirror Master's Mirrorverse without warning. Mirror Master attempts to kill him, but Captain Cold pushes him out of the Mirrorverse and he dies.