Toho omitted Rodan, Varan, and Mogu, electing only to keep Godzilla, Gigan, and Ghidorah. Anguirus was subsequently added to give Godzilla an ally, making the central conflict a two-on-two battle.

Mothra and Mothra vs. Godzilla. Since both Mothra and Anguirus have been utilized in versus-themed Godzilla stories, it's worth wondering why Rodan was never utilized in a greater capacity.