- "Somehow they're increasing the Earth's mass, clouding the atmosphere with particulates. Oh my god. They're terraforming."
"What's that?"
"Planetary engineering. Modifying the Earth's atmosphere and topography." - ―Dr. Hamilton and Carrie Farris[src]
"Terraformation" is the process of modifying and reshaping the environmental composition of a planet or other celestial body to make it habitable for life. Most humanoid life that engage in terraforming modify the world to meet criteria for their own species.
History
Invasion of Earth
Steppenwolf of Apokolips utilized the Mother Boxes' energy, called the Unity, to reshape conquered planets. Thousands of years ago, he attempted to conquer Earth in Sector 2814 during his crusade, but was forced to retreat after the forces of Earth, including the Olympians and the Sector's Green Lantern, successfully drove back the New God and his Parademons.
Steppenwolf lost the three Mother Boxes he'd brought with him to Zeus, who then entrusted them to the Amazons, Atlanteans, and Humans.[1]
Kryptonian expansion
- "Long ago, in an era of expansion, our race spread throughout the stars seeking new worlds to settle upon. This scout ship was one of thousands launched into the void. We built outposts on other planets, using great machines to reshape environments to our needs. For 100,000 years, our civilization flourished, accomplishing wonders."
- ―Jor-El[src]
World Engines were used to terraform Kryptonian colonies for settlement.
In their era of expansion, thousands of worlds were colonized to spread Krypton's people throughout the stars. Explorer Guild pilots, such as Kara Zor-El, were trained extensively to learn how to survive in possible environmental conditions in preparation for their joining the Great Age of Exploration, as it was known then.[2]
After scouting planets for habitation, World Engines were sent in to reshape the planets' environments to fit the needs of Kryptonians, adding particulates into the atmosphere and changing the planets' gravitational poles as needed.[3]
Battle of Metropolis
- "If Krypton lives again, what happens to Earth?"
"A foundation has to be built on something, Kal. Even your father recognized that." - ―Superman and General Zod[src]
The Black Zero working in tandem with a World Engine
33 years following the destruction of Krypton, war criminal and Sword of Rao leader General Dru-Zod attempted to terraform Earth, using a World Engine in tandem with the Black Zero prison frigate to create a New Krypton. The World Engine landed in the Indian Ocean, where it rebounded the gravitational beam from the Black Zero in Metropolis, filling the atmosphere with particulates. However, the attempt failed when Superman destroyed the World Engine.[3][4]
Steppenwolf's return
- "No protectors here. No Lanterns. No Kryptonian. This world will fall - like all the others."
- ―Steppenwolf[src]
Earth successfully terraformed into Apokolips in a possible future.
A year and a half[1] after the death of Superman, Steppenwolf returned to Earth, where he had been humiliated and defeated thousands of years ago by Zeus and the armies of Earth. His communion with Lex Luthor informed him that the world was entirely vulnerable, as Superman was dead, and no Green Lanterns were present to intervene like during his previous attempt at conquering the world. Steppenwolf devised a plan to unite the lost Mother Boxes on the planet, fusing them together to form the Unity, whose power he would then use to reshape the planet into one similar to Apokolips.
However, the Justice League, established shortly before his arrival, was preparing their assault on the New God. After his revival, Superman and Cyborg successfully separated the Mother Boxes, ending the threat of planetary annihilation, sending Steppenwolf and his Parademons away through a boom tube.[1]