Film
- The post credits scene reveals the name Metphies whispered to Haruo of the creature that destroyed his people's civilization and is supposedly so much worse than Godzilla that the mere fact he's fighting Godzilla instead is reason enough not to be afraid. GHIDORAH.
- He makes his debut in the third film, and he is a literal Planet Eater. He's an extradimensional Eldritch Abomination taking the form of three serpentine astral projections emerging from three portals in the sky, and his three necks stretch twenty kilometers long.
Novel
- Rodan returns. This time, a swarm of these flying Kaiju make Rome into their personal feeding ground.
- In the future, Godzilla Earth rules the entire Earth with no other Kaiju present other than his offspring. The terrifying part is that in the past, there was Destroyah and Gorath who's implied to be Kaiser Ghidorah. We now learned that Godzilla Earth decimated Gorath with a Spiral Ray and it's implied that Godzilla Earth killed Destroyah. How powerful is this Godzilla?
- The United Earth was preparing to begin Operation Great Wall, the same plan Godzilla easily demolished. We have a very clear idea how hard it was to lure Godzilla to the trap as the forces assigned to that task had to deal with an entire species of Griffon, Giant Condor, Giant Rats, Kumonga, Kamacuras, Meganula and a Rodan. It's big sign that more Kaiju are taking over the planet and foreshadowing Godzilla's eventual rule.
- China also had it just as bad as Africa as there are swarms of Meganula, Rodan and a Gorosaurus.
- Humans did the impossible and managed to imprisoned Godzilla.....for a year. Unknown to everyone, Godzilla doesn't just feed on nuclear energy, he could also feed on magma as well. Having absorbed enough, Godzilla finally escaped and he is not happy.
