Grand King Ghidorah's young form, Cretaceous King Ghidorah (白亜紀キングギドラ?, Haku Aki Kingu Gidora), first arrived and attacked the Earth130 million years ago in the Cretaceous period. Cretaceous King Ghidorah quickly caused the KT extinction event; he exterminated the dinosaurs and almost every other life form on the planet. Cretaceous King Ghidorah then encased himself within a meteor and left the Earth, using the life-essence of the creatures he had destroyed to live as he traveled through space. Millions of years later, during a meteor shower in 1999, the same meteor crashed into the Mt. Fuji region, with Cretaceous King Ghidorah now being in his Grand King Ghidorah form. Mothra Leo, as Rainbow Mothra, came in and attacked Grand King Ghidorah, but ended up being overpowered by Grand King Ghidorah. Then, with the aid of his priestess Moll, Leo transformed into Light Speed Mothra and traveled back in time to battle Cretaceous King Ghidorah, when he wasn't as powerful. During the battle, Leo cut off one of Cretaceous King Ghidorah's tails and the tail burrowed into the ground, which would regenerate an entire Grand King Ghidorah body millions of years later. Cretaceous King Ghidorah was defeated when Rainbow Mothra used paralyzing powder on him and then dropped him into an active volcanic Mt. Fuji, destroying the first Cretaceous King Ghidorah.
Grand King Ghidorah
130 million years layer, Cretaceous King Ghidorah arose again as Grand King Ghidorah. It came to Japan to feed on humans, mainly children, but he soon started to eat adults. Rainbow Mothra heard of this monster, and he quickly took action to defeat it. Even with all of Rainbow Mothra's power, Grand King Ghidorah quickly defeated him. Rainbow Mothra retreated home, and was transformed into Light Speed Mothra and he flew through time to destroy Grand King Ghidorah in his weaker form, Cretaceous King Ghidorah. He defeated the young form of the Ghidorah, but Grand King Ghidorah's tail dug into the ground, and regenerated his body over millions of years. Grand King Ghidorah returned, only one day later than he arrived the first time. Rainbow Mothra was then reborn as Armor Mothra, and he engaged Grand King Ghidorah in battle. After a long battle, Armor Mothra destroyed Grand King Ghidorah once and for all.
Cretaceous King Ghidorah
Cretaceous King Ghidorah can spit fireballs from his mouths.
Cretaceous King Ghidorah can fly at the speed of mach 3.
Cretaceous King Ghidorah can release hurricane winds from his wings.
Cretaceous King Ghidorah can travel in space by encasing himself within a meteor using the extracted life essences he consumes.
Cretaceous King Ghidorah is able to grow his body back from severed parts.
Grand King Ghidorah
Grand King Ghidorah flies at the speed of mach 3.
Grand King Ghidorah releases hurricane winds from his wings.
Like King Ghidorah, Grand King Ghidorah can also fire Lightning Beams and Gravity Beams from the mouths of all 3 of his heads.
Grand King Ghidorah is able to fly even with the loss of one of his wings using a zero gravity field.
Grand King Ghidorah's scales can manipulate the light from projectiles to form a protective barrier.
Grand King Ghidorah can shoot six bolts of electricity from each of his wings.
Grand King Ghidorah is able to create a dome that allows objects to pass through, yet has a corrosive effect when they try to leave & the dome's exterior is laced with tentacles.
Grand King Ghidorah can teleport smaller beings inside the dome.
Grand King Ghidorah is able to travel in space by encasing himself within a meteor using the extracted life essences he consumes.
Grand King Ghidorah can install a weak mind control.
Grand King Ghidorah, specifically in his weaker Cretaceous King Ghidorah form, single-handedly caused the extinction of the dinosaurs and over three-fourths of all species on Earth at the end of the Cretaceous period.