Gyaos, giant pre-historic reptilian man eating birds.
Gamera, a giant tutrle that flies.
Gyaos wants to destroy the world, Gamera wants to protect us, and fight Gyaos.
Dumb humans attack Gamera.
What more can one ask for?
Yup, suspension of belief is needed when dealing with Kaiju. But lots of goofy fun to be had while you are at it.
If you think Godzilla is cool and fun then check out Gamera.