*Lex Luthor's control of Captain Marvel comes courtesy of equipment developed by the original mad scientist, Dr. Sivana. The worms that manipulate the mind of the wizard Shazam's protege are also a nod to another of the Captain's foes: Mr. Mind.
Writer Mark Waid reveals that Luthor may have taken the technology against Sivana's will -- perhaps even over his dead body. *Source: Back of card