Action Comics #544

Direct

Barely alive after his latest fight with Superman, Luthor heads to Lexor to recover, where he meets his son for the first time. Meanwhile, back on Earth, one of Luthor's robots takes revenge in his master's stead. While Superman figures out how to deal with the revenge plot, Luthor stabilizes the core of Lexor with a \"neutrarod\" so it is not destroyed by internal stresses. Superman finally arrives on Lexor to fight once again with Luthor, but in the fight Luthor disrupts the rod, destroying the planet and killing his wife and son.