As for why Toho didn't go down that road, it's likely that the concept became unnecessary ... the Three-Headed Monster, Godzilla vs. Mechagodzilla II, and Godzilla: Final Wars.

It took a lot of work and designs to get Godzilla the way he looks in the final movie. Many of the early concept designs for Godzilla are shown in a new book out this week, "Godzilla: The Art of ...

Had things worked out differently, Anguirus could have enjoyed a much more prominent presence in Godzilla's universe.