Cron's species

Cron's species is an unnamed, Precambrian, hyper-advanced, extragalactic, gas-based sapient shapeshifting species, two of which were responsible for the creation of life on Earth.

Biology
Cron's species, in their true forms, appear to be clouds of purple gas, with yellow energy arcs flashing throughout their bodies. They are capable of shapeshifting into solid humanoid forms, including forming clothing and armor, and in these forms, can fire energy beams that can reconstruct molecules, capable of changing the composition of lifeforms into something entirely alien, and can change the chemical composition of air into toxins. Cron's species is capable of flying in any form, implanting thoughts into one's subconscious, and of reading minds, which allows them to both speak telepathically and learn entire languages from a single being. Their lifespans stretch over several billion years, and they appear able to both fly through and survive in space without any needed life support equipment, likely due to their gaseous physiology. They are known to have at least two genders, male and female, although any possible form of reproduction is unknown.

Culture and society
Little is known about the culture of Cron's species, only that they have been known to seed life on planets and guide their evolution to create complex, sapient beings. Male and female individuals are known to pair up in a marriage-like unison, and will seed life together, although a shared goal does not stop them from fighting over how to seed and guide life, and spouses are not above destroying the biosphere of planets their mate has worked on to reshape it to their image. However, they are all known to have a sort of parental connection to the planets they alter, and will work to preserve the planet's potential to hold life, although they have not been seen directly intervening in the affairs of the native sapient species. The language of this species is unknown, but is presumably unable to pronounced by Humans or Kryptonians, with at least some words, such as Cron's true name, having no English translations.

Technology
Cron's species has access to incredibly advanced technology, with the only known example being large devices known as Power Prongs. Power Prongs, resembling Y-shaped metal towers with a central antennae, can disguise themselves as trees and emit radiation that is visible to Kryptonians, but is invisible to other members of Cron's species, making them unable to detect them. They are capable of reshaping planetary biospheres to fit the environments that the Prongs' users desire, but only one Power Prong can work on a planet at any point in time. For another Power Prong to be inserted, the first must be removed or otherwise rendered unable to function, or it will cancel the effects of the second. Only other members of Cron's species can remove or destroy the Power Prongs, as they are protected by a forcefield that even Kryptonians cannot break. If attacked, they can transmit "Trosm-rays" that give a telepathic message from the Prong's user to the attacker.

History
Cron's species arose several billion years ago in an unknown galaxy. Two members of this species, a male named Cron and a female named Nutra, joined together as mates and began seeding life on many forming planets, although the two would often come into conflict over how to reshape worlds. Nutra came across Earth, which was still a molten ball, and used her Power Prong to start reshaping the planet into something that could support life, guiding the evolution of life to create Human beings, although Cron disapproved of her methods and goals. Several billion years later, in 1981, Kal-El, a Kryptonian living on Earth under the name Clark Kent and acting as the superhero Superman, came across Cron in the Rocky Mountains, who had returned to Earth. Cron used his abilities to convert trees into alien lifeforms composed of compounds not native to the Milky Way, presumably an image of what Cron desired for Earth. Cron scanned Superman's mind, gaining the knowledge of how to speak English, and told Superman that his purpose on Earth was to reshape the planet to something with a greater potential for the future, not destroy it. However, Cron was unable to find Nutra's Power Prong, so he plants a subconscious image into Superman's mind of the Power Prong. Cron then converts air around Superman into argon and methane, and Superman is forced to fly fast enough to create a vortex that could send the toxins into space before they can harm any living beings, giving Cron the chance to vanish. Superman continued to receive thoughts of the Power Prong, eventually going to his computer in the Fortress of Solitude to investigate. Using the computer to read his mental image, the computer determined that the Power Prong was some sort of power source. Superman scoured the Earth for the Prong, eventually finding it somewhere in South America due to the radiation emitting from the Prong, which was disguised as a tree. Superman, assuming that the Prong was giving Cron his power, attacks it, but only strikes a forcefield, activating a message from Nutra, who reveals her part in the creation of Earth's life and the true purpose of the Power Prong, which is creating Earth's life-giving conditions. Cron then appears, as he had used Superman to lead him right to Nutra's Prong, with his own Prong hidden in orbit. Cron revealed his goal of reshaping Earth's biosphere to his liking to Superman, channeling his energy through his Power Prong to start breaking through the forcefield of Nutra's Power Prong. Unable to stop Cron due to the forcefield around Cron's Prong, Superman came up with a strategy based on seeing that the conflict between Cron and Nutra appeared to be one of parents arguing over how to raise a child. Knowing what to do, he returned to the Fortress of Solitude, and retrieved a Rigellian Plasmo-bomb, a device capable of destroying Earth in an instant. Superman ordered Cron to stop his terraforming, or else he would push the detonator button. Cron, reading the truthfulness in Superman's mind, agreed to leave the planet with his Power Prong, leaving Nutra's intact, deciding that an Earth Nutra made was better than no Earth, confirming Superman's thought that Cron had a parental instinct to protect Earth's capability to hold life, even if he didn't like the way it turned out. Unknown to Cron, Superman had removed the filament that could enable the Plasmo-bomb to detonate, as all he said was that he would push the button, not that the bomb would actually detonate.

Appearances

 * Superman Volume 1 #358 (1981)