[Daikaijuman54]

Well Godzilla's Toku, and the first example I could think of was this:

Godzilla X Varan, Anguirus, and Baragon: Giant Monsters All Out Attack.

Sound familiar? It was the original draft for Godzilla, Mothra, King Ghidorah: Giant Monsters All Out Attack, which Shusuke Kaneko (the Heisei Gamera Trilogy) proposed to Toho. As you can imagine from the title, Toho switched out Varan and Anguirus for Mothra and King Ghidorah in hopes of making the movie more marketable after Godzilla X Megagiurus underperformed. It turned out to be a success as it was the highest grossing Millennium Godzilla Film (and one of my favorite Godzilla movies of all time).

Fun Fact: The suit designer, who was disappointed that his all-time favorite monster, Varan, didn't make the cut, added his head fins onto King Ghidorah's design for the film.