The game is composed of a total of eight levels, spanning from the beaches of Florida to the floating island of Manhattan to the Technodrome , ultimately concluding with Shredder's lair and finally to Krang's Spaceship.   The game's regular enemies include a variety of Foot Soldiers , as well as Giant Mousers and Stone Warriors. The game's bosses include villains from the cartoon series and toyline such as Dirtbag, Groundchuck, Slash , and Leatherhead , in addition to the return of Shredder and Krang , along with Bebop and Rocksteady . Tokka and Rahzar from the film Teenage Mutant Ninja Turtles II: The Secret of the Ooze also appear, alongside Shredder's mutated counterpart from the film, Super Shredder, as the game's final boss. Despite being featured on the cover, there are no Triceratons in the game. 
Compton asked theoretical physicist J. Robert Oppenheimer of the University of California, Berkeley, to take over research into fast neutron calculations —the key to calculations of critical mass and weapon detonation—from Gregory Breit , who had quit on 18 May 1942 because of concerns over lax operational security.  John H. Manley , a physicist at the Metallurgical Laboratory, was assigned to assist Oppenheimer by contacting and coordinating experimental physics groups scattered across the country.  Oppenheimer and Robert Serber of the University of Illinois examined the problems of neutron diffusion—how neutrons moved in a nuclear chain reaction—and hydrodynamics —how the explosion produced by a chain reaction might behave. To review this work and the general theory of fission reactions, Oppenheimer and Fermi convened meetings at the University of Chicago in June and at the University of California, Berkeley, in July 1942 with theoretical physicists Hans Bethe , John Van Vleck , Edward Teller, Emil Konopinski , Robert Serber, Stan Frankel , and Eldred C. Nelson, the latter three former students of Oppenheimer, and experimental physicists Emilio Segrè , Felix Bloch , Franco Rasetti , John Henry Manley , and Edwin McMillan . They tentatively confirmed that a fission bomb was theoretically possible.