In the American version, the scene where the film of Gojira's first attack on Tokyo is shown has several seconds added on to it as well as stop motion footage provided by Warner Bros. Also, the film adds narration to the sequence.
The 2007 Sony U.S. DVD release features the original Japanese version and the U.S. dubbed version. The U.S. version featured on the disc is not the original theater version but a video version in which the main title "Gigantis, the Fire Monster" is replaced with the title "Godzilla Raids Again." It retains the original U.S. dubbing in which Gojira/Godzilla is referred to as "Gigantis."
Because Gojira/Godzilla was referred to as "Gigantis" in the American version, its roar was changed to state it was not the same monster from the first movie as well as backing up claims that Gojira and Anguirus originated from the same family of dinosaurs. The traditional Gojira roar was replaced with one of Anguirus's roars while a different toned roar was kept for Anguirus. The Japanese version used Gojira's traditional roar and used both tones for Anguirus's roar.
The American version was narrated from beginning to end by the character, Shoichi Tsukioka. The Japanese version was left without the narrations.