Eco-structuring

Even though Cybertronian life-forms are quite capable of surviving on purely organic worlds, they sometimes resort to eco-structuring to feel more at home. Eco-structuring is the process of converting a planet into an environment hospitable to mechanical lifeforms, particularly those from Cybertron. It can be performed rapidly through devices capable of converting organic matter to technological matter, such as the Key to Vector Sigma. It can also be performed manually in a much more gradual process, such as that performed by the Cybertronian Empire in the construction of the Hub.

It is also known as exo-structuring, cyberforming, or mechaforming.

Marvel Generation 2 comic
The Cybertronian Empire, believing organic life to be little more than bacteria and viewing mechanical life as the pinnacle, spent untold millennia eco-structuring worlds. They believed this to be construction rather than genocide. The indigenous lifeforms were clinically exterminated, and a metal casing for the planet was manually built. This apparently could be done quite quickly.

When they first reported their findings to Optimus Prime, Grimlocok and his Firestormer team had encountered seventeen "little Cybertrons".

Beast Machines cartoon
In the time of Megatron's Vehicon-powered rule over Cybertron, the Oracle revealed that even Cybertron itself was not originally technological, but had been an organic world cyberformed.

Dreamwave Generation One continuity
Megatron released a metallic virus that converted everything it touched — land, machines, people — into metal in an effort to remake Earth more like Cybertron.

Cybertron cartoon
The Cyber Planet Keys possess the power to remake planets.

Titan Magazines movie comics
The AllSpark was established as being capable of cyberforming a planet. The Decepticons tried to use its power to cyberform Earth into a new Cybertron, but they were foiled by the Autobots.

Age of Extinction film
The detonation of a seed cyberformed anything caught in its blast radius. Circa 65 million B.C.E., the "Creators" detonated seeds upon thousands of planets to create vast quantities of transformium. On Earth, their cyberforming campaign triggered the extinction of the dinosaurs. In the present day, Transformer bounty hunter Lockdown, having been hired by the Creators, entered into a deal with the human corporation KSI and Harold Attinger's corrupt CIA taskforce Cemetery Wind: capture Optimus Prime in exchange for a seed. After the deal was complete, the revenant Decepticon leader Galvatron tried to steal the seed in order to build a new Decepticon army and destroy humankind, but he was ultimately foiled by the Autobots and their human allies. Optimus Prime then took the seed with him into space so that it could never be used for evil.

IDW Generation 1 continuity
The plans of the Cybertronian scientist Jhiaxus under the guidance of Nova Prime culminated in the planet of Gorlam Prime being converted to mechanical life, its surface being restructured to resemble Cybertron.

The Decepticons cyberformed planets during the days of the Decepticon Empire, among them B'lahr 39 where Fulcrum served as project manager during the conversion. The process was interrupted by an Autobot attack and may not have been completed. The Phase Sixer Black Shadow was handpicked by Megatron to sterilize planets ahead of the cyberforming process. Before going rogue, Deathsaurus was renowned for turning organic worlds into shiny new "mini-Cybertrons."

Wings Universe
Setting up a secret base on the unremarkable and barren planetoid Qre as part of his experiments towards restoring the Cybertronian Empire, Jhiaxus transformed at least a portion of Qre's surface into a metal-covered one much like that of Cybertron.

Prime cartoon
Megatron planned on cyberforming the Earth using the Omega Lock into another metallic planet so that he could rule both Cybertron and Earth. The first energy pulse to be fired from the Omega Lock created the fortress Darkmount in Jasper, Nevada. However, Megatron's plan was thereafter foiled by Optimus Prime, who destroyed the Lock to protect Earth.

When an attempt to clone an army of Predacons went awry, Shockwave discovered that their remains mixed with synthetic Energon created an imperfect form of cyber-matter. Megatron subsequently revived his old plan of using the Omega Lock to cyberform Earth, and with Ratchet's help in perfecting the synthetic Energon , he nearly succeeded until he was killed in a final battle for both Cybertron and Earth.

Go! cartoon
After reawakening and acquiring the Legendiscs, the Predacon Emperor Dragotron began using their power to start turning Earth into a metal planet. However, Isami Tatewaki and Tobio Fūma had copied the power of the Legendiscs into their own hearts and enabled the Swordbots to eventually defeat Dragotron, with a little help from Optimus Exprime. The cyberforming disappeared, and the Autobots then sealed Dragotron away once more.

Transformers: Devastation
During Cybertron's Golden Age, Nova Prime and his crew set out aboard the Proudstar to seek out uninhabited planets and use plasma energy combined with the Insecticons to Cyberform them, making them capable of supporting robotic life in a bid to create further Cybertronian colonies. However, exposure to a dark force corrupts most of the crew, and they prepare to begin Cyberforming worlds already supporting indigenous life forms. The plot is ultimately stopped when Kranix forces the ship to crash into the Earth. In the present day, Megatron discovers the Proudstar and attempts to use it to Cyberform Earth, with much of New York City being encased in metal until the process is stopped by Optimus Prime destroying the Ferrotaxis.