Mechu-deru represented a dark side Force power that granted the user an innate and profound understanding of how mechanical systems function. The Sith were the originators of this skill, which enabled those who mastered it to wield influence over both inanimate objects and robotic entities. Through the application of mechu-deru, mechanical entities could be brought under the control of the user and infused with the very essence of the Force. Furthermore, this dark side ability facilitated the creation of machine-organic Sithspawn mutants known as technobeasts.
Due to its Sith origins, members of the Jedi Order generally avoided mechu-deru, limiting its practice to a select few Jedi tech specialists. Even within the ranks of the Sith, mechu-deru remained a relatively obscure technique, known only to a handful of individuals at the time of its inception. During the period of the New Sith Wars, the Dark Lord Belia Darzu developed her own unique version of mechu-deru, which she called mechu-deru vitae, and used it to generate an army of technobeasts through the deployment of a nanogene virus. Centuries afterward, the secrets of Lord Darzu were discovered by Cronal, an operative of the Galactic Empire who employed mechu-deru on both mechanical devices and living beings, including himself.
Mechu-deru, a dark side technique, empowered its user to manipulate mechanical systems by channeling the power of the Force. The use of a specifically engineered cybernetic brain implant enabled a Force-sensitive individual to rapidly achieve mastery over mechu-deru.
Through the application of mechu-deru, practitioners could instinctively grasp the operational principles of machinery and circuitry. With mechu-deru, technology could be modified to perform functions beyond its original design, even enabling mechanical devices, including droids, to detect individuals attuned to the Force. Users gained the capability to transform robotic machines into extensions of their own will, overriding their internal control systems. Attempting to seize control of a cyborg's body would result in a dramatic alteration of their cybernetics, causing them to expand into a network of tendril-like appendages. However, such actions carried the risk of backfiring, potentially causing the victim's mechanical implants to turn against the user. Mechu-deru facilitated the fusion of inanimate and living matter, resulting in the creation of part-machine, part-organic hybrids referred to as technobeasts. By employing mechu-deru, it became feasible to imbue these technobeasts with the dark side of the Force, binding them to the will of their creator. Furthermore, the technique allowed users to reconstruct and replace their own body parts with cybernetic enhancements.
Millennia prior to the Great Sith War, adherents of the dark side-oriented Sith Order discovered a method for manipulating mechanical constructs through the power of the Force. This method, known as mechu-deru, was practiced only by a small number of Sith magicians at the time, leading to the obscuring of its secrets. Nevertheless, those Sith who mastered mechu-deru employed it to create metal-flesh hybrids called technobeasts.
In 1250 BBY, during the Sictis Wars within the larger New Sith Wars, a Dark Lord of the Sith named Belia Darzu investigated mechu-deru alongside the dark side art of Sith alchemy. In doing so, Lord Darzu developed a technovirus that could transform living beings into technobeasts. To generate these Sithspawn creatures, Darzu conceived and utilized an alternative form of mechu-deru called mechu-deru vitae. Using the power of mechu-deru, Darzu imbued the creatures with the dark side, binding an army of them to her will. During her time, the Dark Lord documented her knowledge of mechu-deru within a Sith holocron. The creation of Darzu's technobeasts ceased when she was assassinated by the Mecrosa Order, leading to the presumed loss of her secrets.
In the period following the New Sith Wars, mechu-deru was practiced by a Sith Lord known as Darth Maul. Specifically, Maul used the technique to modify a protocol droid designated C-3PX, turning it into an assassination droid.
Centuries after the New Sith Wars, Cronal, a dark side practitioner serving the Galactic Empire, came into possession of a number of Sith scrolls containing the knowledge of Belia Darzu. Intending to use the scrolls for his own purposes, Cronal practiced mechu-deru during his time as the Emperor's Hand, a personal agent of the Galactic Emperor Palpatine. Using his knowledge, Cronal enhanced the thaissen crystals installed in the Force detecting devices used by Imperial Jedi hunters. This allowed the devices to determine the Force-sensitivity and alignment of a specific target.
Following Cronal's unsuccessful Imperial campaign on the planet Mindor, the Dark Side Adept used mechu-deru to replace most of his body with cybernetics, leaving only his head and neck as organic components. Around this time, Cronal spent years experimenting with both mechu-deru and Sith alchemy on the planet Trailia, combining them to create his own method of creation known as the Stygian Art. In doing so, Cronal transformed the native inhabitants into technobeasts, eventually departing with his creations to the world of Coruscant.
Later, Cronal resided on the industrial planet of Andooweel, having fully embraced mechu-deru under the alias "Perek". While operating from an abandoned droid depot, Cronal was pursued by the Jedi Knight Luke Skywalker. During Skywalker's brief period of servitude under the resurrected Emperor Palpatine, the Jedi Knight's cybernetic hand became corrupted by the power of mechu-deru. The alchemical modifications made to Skywalker's robotic limb ultimately led him to a confrontation with Cronal. In an attempt to possess the Jedi Knight, Cronal infected the circuitry of Skywalker's hand with technobeast nanodroids. This attempt backfired, however, when the cybernetic hand turned against Cronal and strangled him to death.
The Jedi king of Ganath employed this power to control his cyborg body and prevent Sidious from entering Anakin Solo.
The power of mechu-deru was also wielded by Irek Ismaren, the son of another Imperial agent and dark side practitioner named Roganda Ismaren. Following the failure of Roganda's scheme against the New Republic, she, like Cronal, somehow acquired a number of Sith scrolls containing the knowledge of Belia Darzu. Around this time, Irek developed an accelerated mastery of mechu-deru through a cybernetic brain transplant, the subelectronic converter. Left unchecked, the Ismarens had the capacity to create and unleash a horde of part-machine, part-organic mutants upon the galaxy.
In contrast to the Sith, members of the Jedi Order were less inclined to integrate technology with the Force. Wishing to avoid following the path of the Sith, the Jedi steered clear of mechu-deru and the study of droids. Despite this, certain members of the Order, particularly Jedi Sentinels operating as tech experts, still practiced mechu-deru. Such specialists were rare within the Jedi Order, known for their ability to disassemble and reassemble various types of technology. Furthermore, details about mechu-deru were mentioned in The Jedi Path, a guidebook for Initiates of the Jedi Order. During the Yuuzhan Vong invasion from beyond the galaxy, the Jedi Knight Tam Azur-Jamin referenced mechu-deru in an essay titled Droids, Technology and the Force. The document explored the Jedi's perspectives on mechu-deru and the potential relationship between mechanical constructs and the Force.
Mechu-deru was first introduced as an unnamed Force ability in Tales of the Jedi Companion, a roleplaying supplement published by West End Games in 1996. This was later retconned by Abel G. Peña, who identified mechu-deru in an adventure seed called The Lost Art featured in the 2001 article The Emperor's Pawns. The name mechu-deru came from The Essential Guide to Episode I, a cancelled addition to the Essential Guide series that was to be written by Daniel Wallace. Wallace provided additional backstory for mechu-deru in The New Essential Guide to Droids, a reference book published in 2006. While mechu-deru was designated as a dark side technique in The Complete Star Wars Encyclopedia, its use by the Jedi Order was later confirmed in another reference book called The Jedi Path. Mechu-deru was depicted without a name in "Collapsing New Empires," a comic in the nineteenth issue of the Star Wars Tales series. This appearance was retconned in the final installment of The Imperial Warlords: Despoilers of an Empire, a StarWars.com blog series that concluded in 2014.