During the second season, they did Godzilla vs. the Sea Monster (Ebirah, the god-shrimp) and the anti-classic Godzilla vs. Megalon. So the classic kaiju (I'm not including in this really big American monsters, such as the Amazing Colossal Man or the Deadly Mantis) in the document will be:
Godzilla (a sillier, radiation-free version of my current one)
Gamera (again, a different one than the one on these boards)
Ebirah (the aforementioned godshrimp)
Gaos (again, a different creature than the darker, modern version)
Barugon (rainbow ray-shooting, freeze-tounging giant lizard)
Gigan (the cycloptic cyborb with a buzzsaw in its gut)
Jet Jaguar (a standard Ultraman ripoff)
Guiron (the Ginsu-knife kaiju)
Zigra ("On Earth, they live on land and eat what lives in the sea. On Planet Zigra, we live in the sea and eat what lives on land!")
and Megalon (It's a cockroach with drills for hands and a lightning-shooting horn that spits fire bombs. Makes sense to me.)
Demiurge out.