With the huge success of Nygma's latest creation, "Riddle of the Minotaur", millions were made for both Competitron and Daniel Mockridge. However, when Mockridge refused to pay Nygma his share of the profits, Nygma threatened to sue him for royalties. Mockridge, however, responded by firing him and gleefully showed Nygma the Work for Hire contract he had tricked him into signing long ago. It basically gave Mockridge all rights to any game Nygma created, therefore informing him that no matter what, he had lost. Infuriated, Nygma vowed revenge, and Mockridge smugly brushed it off, convinced his company's future was secure with Nygma's millions.
Still scheming for a wealthy retirement, Mockridge opted to sell Competitron to Wayne Enterprises, since Bruce Wayne wanted to bring the company to Gotham to provide jobs for the unemployed. Unfortunately, Mockridge's big mistake came back to haunt him when Nygma, now going by the name "Riddler", used a riddle to summon Mockridge into a trap in his own nightclub, The Wasteland. Mockridge offered to pay Nygma his money once he had sold the company, but he refused, claiming it was Mockridge himself he wanted. With this, the Riddler's thugs captured Mockridge and took him away to a giant-sized maze based on "Riddle of the Minotaur" in an amusement park. Mockridge was strapped to a table just underneath the sword of the robotic Minotaur, programmed to kill him at 4:30 AM.
Batman and Robin thwarted the assassination attempt and rescued Mockridge, although the Riddler escaped Gotham unharmed. Mockridge eventually sold Competitron for ten million dollars, guaranteeing a wealthy life, albeit not a satisfied one: to the amusement of Batman and Robin, Mockridge would from then on live in constant fear of the Riddler's eventual return.