[Source] Quadex power cores were a type of power core. The Millennium Falcon, a customised YT-1300 light freighter owned by the junk dealer Unkar Plutt and then the smugglers Han Solo and Chewbacca, was equipped with a Quadex power core. Around thirty years after the Battle of Endor, a flux in the starship's motivator bled into the power core, causing a series of issues that led to gaseous fuel filling the ship until the problem was fixed by the scavenger Rey.