Godzilla Vs. Gamera (Godzilla Vs. Gamera: Kaiju Showdown in Japan) is a crossover film between the Godzilla and Gamera franchises.
A mysterious Xilien takes control of Gamera and uses him to destroy Tokyo. The mind-controlled Gamera later arrives on Monster Island, where it fights Zilla, Kumonga, Kamacuras, and Gezora. Although Gamera defeats them, they do manage to scar him and knock him out a bit. Gamera flies off and starts destroying Chicago. However, his mind control is begining wear off, after remembering Zilla and Gezora helping a young child escape. Meanwhile, Gamera had been followed by Godzilla to continue the fight. As Godzilla gets the upper hand, Gamera is commanded to fly off. At the North Pole, Gamera's commander, a Xilien named Ekrilloss, dissapointed by how Godzilla nearly defeated Gamera, gives Gamera some team mates: Guiron, Destoroyah, Orga, and Gigan. On Monster Island, Godzilla finishes fighting a starfish like creature. Suddenly, Godzilla is attacked by Guiron. Godzilla manages to defeat Guiron, but is ambushed and knocked out by Destoroyah, Orga, and Gigan. At the North Pole, Godzilla has a mind control chip implanted in him by Ekrilloss. Godzilla and Gamera are sent to attack Osaka. However, Godzilla then reveals he was never brainwashed the whole time, and he was acting along. After a long battle, Godzilla knocks Gamera into a big building, which causes his mind control chip to malfunction. Free from Ekrilloss' control, the two monsters go to the North Pole. They attack and eventually destroy Ekrilloss' base, killing Ekrilloss, Destoroyah, Orga, and Gigan in the process. With the world seemingly safe once more, the two monsters leave.
- Unnamed starfish-like kaiju (implied to be called 'Hexaitode')