The Penguin had met and struck a deal with the Shredder, who he gathered with at a Gotham shipping yard. The Shredder needed the resonance engine in order to create a portal to get back home. Penguin delivered it to Shredder and was promised a large sum of money. The Shredder lied about their payment, something that Penguin loathed. So he demanded that his hired guns kill Shredder, but his Foot Clan came to their master's aid. Shredder was on the verge of killing Penguin, but the cowardly businessman pleaded for his life. He promised to help Shredder in whatever aid he requires such as money, man power or machinery. So the Shredder decided to allow Penguin to live a little while longer as long as it suited his needs.