It all began in 1954. Humankind, in its greedy blood lust, sought to create the most dangerous weapon imaginable ever since they first split the atom. However, the results were more of a catalyst for a nightmare.

On November 3rd, 1954, Tokyo was laid to waste by Godzilla, the first of many giant beasts mankind would label as 'Kaiju'. After turning Tokyo into a graveyard, Godzilla was seemingly killed by an unknown compound at the cost of its creator. However, that brave man's sacrifice would prove to be in vain.

On April 24th, 1955, Godzilla returned... and he wasn't alone as the second Kaiju, Anguirus, emerged and fought in the streets of Osaka and from then on, the Kaiju just kept coming.

1956 saw the first appearance of Rodan in Kyushu.

On 1958, Hokkaido came under siege by Varan.

1961, humanity was humbled by the appearance of Mothra.

Manda, Baragon, Sanda, Gaira, Gorosaurus, Gezora, Kamoebas, Ganimes, King Ghidorah... more and more just kept coming.

Some, like Mothra and King Seesar, held interest in protecting mankind as benevolent gods, others, such as King Ghidorah, SpaceGodzilla, and Destoroyah, were devils on Earth wanting to make every moment of humanity's existence a living Hell, many were just mere animals trying to survive in the world as best as they could, then there was Godzilla, whose only loyalty was to the world he lived on while humankind could drop dead for all he cared.

Over the years, humanity tried to survive against monsters that shrugged off everything thrown at them, even going so far as to create monsters of their own... only for it to backfire every time. It seemed like hope was a fever dream... until 2020 when something miraculous happened; the Kaiju stopped appearing.

What's more, in the following year, mankind found out they were not alone on the lonely blue marble they called home. A race of humanoids called the Altaeri had been discovered deep inside the Marianas Trench and a bond was forged between them, a bond enforced by the ever remaining fear of the Kaiju returning. Pooling together their resources and technology, humanity and the Altaeri developed a weapon that both species hoped to stand equal to the gods: robotic, mobile suits called Gundams.

With these new weapons at the ready, humanity and Altaeri alike were prepared to fight should the Kaiju ever return...

Or so they thought.