well I already have dibs on Godzilla and Space Godzilla. but besides them the only ones I might hold back on are Gigan, King Ghidorah, Orga, and Monster X (aka Keizer Ghidorah) just because they are aliens I was possibly thinking of making them the bad guys we use the Kaiju we control to fight.

Jet Jaguar, Kyriu, and MechaGozilla II will be controlled by young people from the army.

so available monster are: Mothra, Rodan, Anguirus, King Caesar, Manda, Zilla, King Kong, Ebirah, Baragon, Varan, Titanosaurus, Battra,Megaguirus, Biolatte, Gorosaurus.

there are some lesser monsters, like kamacuras, Kumonga, minillia and some others that are not as well known,