King Ghidorah has returned to Earth with a new ally; SpaceGodzilla. The two plan on unleashing an army of mass-produced MechaGodzilla soldiers to destroy Godzilla once and for all. But that's not all they have planned. Ghidorah has a secret weapon from another dimension, and plans on unleashing it on Earth. Godzilla must take on his greatest challenges yet, but his life will also be changed forever by yet another family secret, as well as his recent marriage to Mothra. This may be his final war.

Mothra has been having nightmares. One in particular was of a traumatic experience from her past. As it turns out, the being who caused this trauma is back, along with the terrifying X, and both are more powerful than ever. They've become so powerful that they cause the unthinkable to happen; Godzilla and Ghidorah team up. But two others from Mothra's past join the battle. Will their combined might be able to defeat the power of X and the monsterous Desghidorah? Featuring Kaiju from the Rebirth of Mothra series, including Mothra Leo and Desghidorah, and the return of Battra. Also featuring Monster X from Godzilla Final Wars, and Hokmuto from Godzilla 2014.