Narrator: Before King Ghidorah invaded Cybertron, we must see how it happened.
[We see the ruins of San Francisco, decimated after the battle between Godzilla and the MUTOs.]
Narrator: The city is riddled with vortexes to Hollow Earth. Out of one, Godzilla rises and roars, for something else is in the destroyed ruins; Ghidorah. One of the heads attempts to sneak behind Godzilla, but his heightened senses allow him to dodge in time. King Ghidorah's three heads stare at Godzilla with disgust. Godzilla charges his Atomic Breath, but Ghidorah uses his lightning bolt projectiles to knock the Titan down. Godzilla tries to get up, but Ghidorah uses wind created by his wings to keep Godzilla down. Godzilla manages to grab the alien's leg and drags both himself and Ghidorah into one of the vortexes.
Narrator: But it didn't take them to Hollow Earth.
[Godzilla falls into a new world, and Ghidorah goes to Cybertron]