The original concept is similar to the finished version of "Terror of Mechagodzilla", with many of the changes being budgetary in nature. The most obvious alteration is the removal of the two dinosaurs called the Titans, which merged to become Titanosaurus in the first draft. It was an interesting concept, although something that was also under-explained, considering the magnitude of such an occurrence of the creatures merging. Another noticeable change to the script is that of the final battle, which does not move to the countryside but instead would have reduced Tokyo to rubble during the ensuing conflict between the three monsters.