- Unicron, debuting in the 1986 animated movie, is an ancient planet-eating Transformer that was created by a Mad Scientist called Primacron. Primacron created Unicron to help him take over the universe, but he rebelled and destroyed Primacron's lab. Unicron travelled through space and devoured many inhabited worlds, including the planet of Lithone. After learning of Optimus Prime's death and his passing of the Matrix of Leadership, Unicron tracked down Megatron and tasked him to destroy it, as it was the only thing that could stand in his way. Torturing Megatron into accepting his deal, Unicron reformatted him into Galvatron and made him more susceptible to his psychic assaults. Galvatron, tired of being Unicron's pawn, tried to use the Matrix to turn Unicron into his slave, but it had no effect in his hands. In retaliation, Unicron started destroying Cybertron and attacked both Autobot and Decepticon alike. Unicron was eventually defeated by a Matrix-wielding Rodimus and only his head remained to orbit Cybertron, a testament to the Transformer that made even the mighty Megatron beg for mercy.
- Beast Wars:
- Megatron is a self-proclaimed tyrant and would-be Galactic Conqueror, who named himself after his world's equivalent of The Antichrist. A user and abuser of his followers, Megatron divides the world into enemies and pawns, killing or enslaving the former, and ruthlessly exploiting the latter. A gloating sadist, Megatron never kills anyone quickly when prolonged torture will do, considers his own allies expendable, and hopes to bring Cybertron, and eventually the galaxy, under his heel. His more notable crimes include extracting half of Rampage's spark, placing it in a vise, and using it to torture Rampage into submission; unsuccessfully ordering Dinobot to kill Quickstrike, one of Megatron's relatively more loyal soldiers, after Quickstrike lost to Dinobot in a sort of re-entrance exam into the Predacons; an aborted genocide of humanity's common ancestor; attempting to rewrite all of his history by killing the original Optimus Prime; and finally, sacrificing all his remaining troops in order to gain control of the Nemesis and set out to overrun the galaxy. His defeat doesn't stop him either—when he returns in Beast Machines he's gotten worse, picking up a serious god complex along the way. Seizing control of Cybertron, Megatron extracts the sparks from everyone on the planet, reducing them to mindless drones. Accquiring a hatred of all organic life, Megatron tries to scrub Cybertron clean of it, resulting in the near destruction of all life, robotic and organic, on his home planet when his last mad grasp for power finally fails.
- Tarantulas is a schemer and backstabber second-to-none. Planted as The Mole in Megatron's operation by the Predacon Secret Police, Tarantulas is a cackling Mad Scientist, who enjoys performing gruesome experiments on his victims, and eating anything or anyone he catches in his giant webs, organic or robotic; he admits to enjoying the act itself more than the meal. He brainwashes several Maximal protoforms into becoming Predacons, most notably Blackarachnia and Inferno, and eventually reveals that he hopes to usurp control of the team from Megatron. Tarantulas later exploits and Mind Rapes Blackarachnia, leaving her with a paranoid terror of him, and later swears a vendetta against her, promising to hunt the other spider down and kill her for daring to defy him. He tries to destroy the Ark, which would create a time paradox and lead to the extinction of the Transformers as a species. Ultimately betraying both sides, Tarantulas is revealed to be descended from neither Autobot nor Decepticon, and he attempts to use alien technology to wipe out all factions, swearing that when he's done with his own species, he will return and commit genocide against the aliens themselves. Void of loyalty or conscience, Tarantulas makes even his own nominal allies uneasy, a fact that he is downright proud of.
- Megatron is the cruel, ruthless leader of the Decepticons and the Autobots' worst enemy. A megalomaniac who overthrew the generally peaceful leader of the Decepticons to make them his own, Megatron spurred them into all-out war against the Autobots, leading to heavy casualties on both sides. Megatron utilized chemical weapons that wiped out entire battlefields—even his own men—and air bombings on civilians during the Great War. After resurrecting himself on Earth, having caused much destruction to regain his body, Megatron makes several attempts to invade Cybertron, culminating in him ordering Decepticon attacks on several Autobot bases throughout the cosmos while he personally invades Cybertron and destroys its Autobot leaders, planning to test his new Omega Supreme clones by first annihilating Detroit.
- Lockdown is a ruthless and sadistic Bounty Hunter whose only loyalty is to himself. Unaligned with Autobots or Decepticons, Lockdown is indiscriminate in his prey, taking commissions from whomever is willing to pay him. To make himself more powerful, Lockdown steals upgrades from his targets, torturing them by cutting the weapons from his victims' bodies. Devoid of empathy, Lockdown sees his victims as little more than trophies, taunting them if he chances to encounter them again. Having once been a student of the Autobot Yoketron, Lockdown murdered his former master in order to steal the protoforms under Yoketron's protection and sell them for his own profit. Merciless and consumed by greed, Lockdown is a sociopath who frightens and disgusts Autobots and Decepticons alike.
- Meltdown, originally Prometheus Black, is a human scientist who ended up mutated by his own experiments. He tries to kill his rival, Isaac Sumdac, in a fit of rage whilst blaming him for all his problems, including his self-inflicted transformation. Later, he becomes so obsessed with creating a human transformer, he not only mutates at least two innocent humans into gruesome hybrids combined with animal parts, he also decides to kidnap Sumdac's innocent eight-year-old daughter as his newest test subject, deciding to experiment on children in general now. When Blackarachnia breaks him out of jail in exchange for him eliminating her organic half, he double-crosses her and tries to destroy her Transformer half - a deed which, if not destroying her soul completely, would have left her with a completely organic body she's disgusted with. He also forces the Dinobots to work for him by painfully burning them with his acidic touch until they follow his commands. He hurt them so badly, that they were willing to turn on Bulkhead and Prowl, their only friends among the main cast, just to stay in Meltdown's good graces.
- Colonel Leland "Silas" Bishop is leader of MECH, a terrorist group researching Cybertronian technology. His crimes include capturing Breakdown, torturing him, trying to have him vivisected, and removing one of his eyes; and allying MECH with Airachnid to get his hands on another Cybertronian, Arcee, and was perfectly willing to let Airachnid kill Jack Darby, a sixteen-year old teenager, and his mother to do it; he even states a few human lives are worth it for Arcee's tech. After his men upload him into the now-dead Breakdown's empty shell, saving his life in the process, he thanks them for that and their years of loyal service by thanking them personally and then slaughtering them. He then, taking the name CYLAS—"CYbernetic Lifeform Augmented by Symbiosis"—betrays the human race to Megatron. Seeing himself as a superior being, he razes a military base just to get Megatron's attention, then attempts to blow up everybody inside Raf's house.
- The aforementioned Airachnid is a self-styled "ex-Decepticon" who spent her time in the Great War capturing, torturing, and slowly killing any Autobots she could find for fun. For certain victims, like Arcee, she'd go out of her way to find people they cared for and murder them before their eyes as part of her fun. After the war left Cybertron, she struck out solo to pursue a new hobby: hunting endangered and soon-to-be extinct speciesor species she will make extinct—for sport and collecting grisly "trophies" of her kills. Should she find an attractive species that isn't endangered, she'll ensure that they are by the time she's done, deciding to make humans her new toys, starting with the teenage Jack Darby. Forced back into serving Megatron, Airachnid barely hides her dissatisfaction, trying to usurp control from Megatron at times. She finally breaks free when she finds an Insecticon hive, murders fellow Decepticon Breakdown along the way, and plans to use her new servants to destroy Megatron. Sadistic, merciless and terrifying while enjoying her atrocities, Airachnid is one of the worst to wear the Decepticon logo.
- Robots in Disguise: Megatronus, once a member of the Thirteen Primes, was locked away for betraying his comrades and murdering Solus Prime. Still having influence outside of his prison, Megatronus causes the Decepticon prison transport ship, The Alchemor, to crash on Earth, unleashing dozens of Decepticons on the planet. Contacting Steeljaw, Megatronus manipulates him into releasing him from his prison, and uses his psychic powers to force one of Steeljaw's soldiers to begin amputating his own arm to convince Steeljaw to work faster. When unleashed from his prison, Megatronus betrays Steeljaw, tries to murder both him and the Autobots attempting to thwart him, and reveals he plans to use the power of Unicron and the Allspark to destroy both Earth and Cybertron in one fell swoop as revenge for his imprisonment. Perhaps once a good person, Megatronus shed any heroic traits and replaced them with pure sociopathy and blind hatred.
- Super-God Masterforce: Devil Z is the Decepticon Emperor. Stealing 8 Transtectors to create an army of humans merged with the power of Transformers, Devil Z later intended to cast aside the Godmasters as tools. Straight up Desecrating the Dead and later torturing his minions, Devil Z happily resorts to blaming his minions when he makes an error or miscalculation. Later when humanity proves themselves to be unpredictable, Devil Z decides that humanity is an existential threat and that he must Kill All Humans. When his own subordinates think he is going too far, he kills them without hardly a second thought, and displays absolutely no remorse for his actions.
- Robots in Disguise (dub only): Megatron is the leader of the Predacons, who arrived on Earth in search of the Autobot Weapon Fortress Maximus under the pretext of raiding Earth for its energy. Upon arrival, he kidnaps Doctor Kenneth Onishi and probes his mind to find the location of Fortress Maximus. After receiving knowledge of the Autobot Protoforms, Megatron corrupts their sparks in order to create his Decepticons. Although initially A Father to His Men to his minions if they prove themselves worthy of respect, he discards these qualities upon his rebirth as the Decepticon Galvatron—absorbing the energies of the Predacon Brothers against their will to power his new body immediately upon his transformation, and later reducing Scourge and the Decepticons to mindless drones for plotting to overthrow him with the use of Fortress Maximus. Galvatron's worst actions, however, came during the finale when, after surviving a battle with Fortress Maximus, he transforms into bat form and drains Fortress Maximus's energy to power himself. He then unleashes his bat swarm to brainwash human children with the goal of enslaving them and repeating the process from planet to planet until he has conquered the universe, threatening to harm the children if Omega Supreme or the Autobots intervene. When the Autobots flee into the Space Bridge, Galvatron sends the Decepticons to pursue with the intention of destroying both groups by collapsing the Space Bridge, not caring if any Predacon gets caught in the collapse, all so he could have the entire planet to himself.
- Unicron Trilogy
- Unicron is a powerful and ancient Transformer who feeds upon worlds and the negative emotions of others. Disguising himself as one of Cybertron's moons, Unicron created the Mini-Cons to escalate the war between the Autobots and the Decepticons. Hoping to consume both sides once he regained enough power from their conflict, Unicron's plans were foiled when the Mini-Cons gained free will and abandoned Cybertron. Once fully awakened, Unicron attacked Cybertron, killed Starscream, and briefly stripped the Mini-Cons of their free will. After being defeated, Unicron returned by devouring the home world of Alpha Q and all of its inhabitants. When Megatron revived him, in hopes of turning him into a weapon, Unicron possessed Megatron and went off to destroy several planets that Alpha Q had managed to restore.
- The aforementioned Megatron, later known as Galvatron, is the brutal commander of the Decepticons. Desiring to destroy the Autobots and conquer the universe, Megatron enslaves Mini-Cons, tries to kill the Autobots' human allies, and tries destroy Earth with the Hydra Cannon. Upon his resurrection, Megatron leads his forces in destructive raids for Energon. Megatron plans to use the element to revive Unicron and use him as a weapon. Megatron uses Unicron's power to subvert the wills of his followers, notably enslaving Scorponok and Starscream. Developing a god complex, Megatron seeks to use the Cyber Planet Keys to accelerate the Unicron Singularity's expansion to end reality and reconstruct it in his own image.
Comic Books (by publication date before the film adaptations)
- Marvel Comics continuity:
- The Transformers:
- Unicron is a powerful planet-eating Transformer and the Arch-Enemy of Primus, the creator of the Cybertronians. Millions of years ago, Primus stopped Unicron's quest to consume all of existence by trapping him within a lifeless asteroid and left to wander aimlessly through space. When Primus was shot during a fight between the Autobots and Decepticons, Unicron heard his rival's scream of pain and made a direct path towards Cybertron. Stopping to devour the planet of Ghennix and its roughly 60 billion inhabitants, Unicron reformatted three of its survivors to be his new heralds. After sending them to retrieve Galvatron from the future, Unicron tortured him in order to gain his compliance. He distracted Primus's forces by siccing his sleeper agents that were planted within Cybertron's population millennia ago. Once he finally arrived, Unicron devastated Cybertron and claimed countless lives, including Primus's. Unicron's rampage left lasting scars on Cybertron's surface and truly earned him the title of the Chaos Bringer.
- Lord Straxus is a brutal Decepticon warlord who took over Cybertron after the departure of Megatron. During his reign, Straxus would have his troops round up any Cybertronian who did not pledge loyalty to the Decepticons and subject them to his smelting pools, where they would be melted down for spare parts while they were still alive. Upon receiving a transmission from Earth, Straxus had the neutral scientist Spanner kidnapped so he could build a space bridge for him. When the bridge started malfunctioning, Straxus sent men after men to their deaths because he was too impatient to figure out what the problem was. He would then forcibly reconfigure Spanner's body to become part of the space bridge, leaving him in constant pain and begging for death. After being reduced to a severed head, Straxus intended to swap bodies with Megatron and crush him in his helpless state. When that plan failed, Straxus forcibly reformatted one of his soldiers into becoming a clone of Megatron and transferred his mind into their body. He would continue to torment the clone and eventually drove him to suicide in his attempts to take over his body. Straxus dispensed no mercy to all sides of the conflict, and promised only death to those who stood in his way.
- Flame is an Autobot scientist who was kicked out of his academy in disgrace after proposing a revival of Megatrons plan to turn Cybertron into a mobile spacecraft. Bitter over his rejection, Flame ignored the warnings of his peers despite the danger his project posed to Cybertron. After discovering an abandoned engine room left behind by the Decepticons, Flame faked his death and continued his research in secrecy. When a test firing of the repaired engines destroyed a section of the city Kalis, Flame transmitted a signal that reanimated the corpses of his fellow Cybertronians and forced them to attack anyone who came close to the city. Flame refused to listen to the warnings of his former colleague, Emirate Xaaron, and tried to kill him when Xaaron attempted to shut down his reactor before it would destroy Cybertron. Flame showed no remorse over turning the victims of his own hubris into his zombie slaves, and only cared about restoring the reputation he deservedly lost.
- Generation 2: Jhiaxus is the ruler of the Cybertronian Empire, but was once just another Decepticon warlord on Cybertron. Believing the war between the Autobots and Decepticons was hindering the progress of their species, Jhiaxus abandoned his sadistic ways and left Cybertron with a legion of Decepticons. He led his empire on a campaign of conquest and genocide, terraforming new worlds and wiping out any "inferior beings" that happened to get in their way. When the Autobots began attacking his outposts, Jhiaxus focused his efforts on eliminating this new threat to his empire. Declaring war on both the Autobots and Decepticons, Jhiaxus's cruel nature began resurfacing as he ordered the slaughter of numerous species to lure the Autobots out of hiding. He managed to track down the base of the Autobots and Decepticons, and sent wave after wave of his men to wipe them all out. When Optimus Prime warned him about the arriving threat of the Swarm, Jhiaxus ordered the destruction of San Francisco simply out of spite. Jhiaxus ordered a second strike that would kill his own men, and crushed the head of a soldier who suggested they retreat. Jhiaxus blamed Optimus for his empire falling apart and refused to believe he was still just as much of a petty tyrant as he was back on Cybertron.
- Alignment unlicensed continuation, by Simon Furman himself: The Liege Maximo finally takes center stage as the final threat that the Autobots and Decepticons had to face. One of the original Transformers created by Primus, the Liege Maximo coveted its divine power and wished to become a god equal to its creator. After creating the Decepticons, the Liege Maximo left Cybertron and formed the Cybertronian empire, who were responsible for wiping out countless species during their conquests. The worlds they conquered were added to the Hub, which would open a portal that would ascend the Liege Maximo to godhood while destroying the universe in the process. After being discovered by an Autobot scout ship, the Liege Maximo ordered its fleet to destroy the Autobots and Decepticons before they could intervene with its plans. It harvested the sparks of its own followers to open the portal, and killed several more Transformers who stood in its way. Utterly indifferent to lives that suffered at its hands, the Liege Maximo embraced its dark nature on its path to godhood.
- The Transformers:
- Dreamwave Generation 1 Series:
- Megatronus Prime, debuting here, is known as the Fallen. Created by Primus as one of the original Thirteen Primes, the Fallen became obsessed with the notions of entropy and decay, ultimately attempting to murder his creator after betraying him to Unicron. Escaping the prison he was trapped in some seven million years before the 21st century, The Fallen visited the G1 continuity, gathered several Decepticon outcasts and kidnapped four Transformers, through which he tried to channel enough energy to break the Seal of Primus, awaken Unicron, and end all reality, boasting that his victims were but "casualties in the wars of the Gods". Sharing his master's unquenchable thirst for destruction, The Fallen is precisely the kind of servant that Unicron most needs.
- General Robert Hallo was the head of military development for the United States Army. Obsessed with the idea of controlling the Transformers, Hallo had Adam Rook create a program that could remove the free will from Transformers, and hatched a plan to blow up the Ark II and gain a new robot army. After killing a man who attempted to blow the whistle on the plan, Hallo successfully destroyed the Ark II, killing all the humans on board and sending the Autobots and captured Decepticons into the Arctic Ocean. However, Adam decided to keep the program for himself, and disappeared not long after. Years later, after discovering Rook has been using the program to build a criminal empire, Hallo convinced Spike Witwicky to revive Optimus Prime. However, when showed that he had free will and refused to follow Hallo's orders, he had Optimus, his Autobots and the Decepticons hit with an air strike, intending to kill them all. Unfortunately for Hallo, not only did they survive, an enraged group of Decepticons began rampaging through San Francisco. To be rid of the Transformers once and for all, Hallo ordered the city to be nuked, and when Spike burst in to stop him, Hallo holds him at gunpoint and forces him to watch as the city and Transformers are destroyed. When Spike accused him of only caring about power, Hallo agreed with him, saying power is the only thing keeping Spike and his family safe.
- The aforementioned Adam Rook, aka Lazarus, is just as bad. After designing a program that would remove the free will from Transformers, Adam decided to render the deaths of everyone aboard the Ark II meaningless by stealing the program and disappearing before Hallo had a chance to use it. Motivated by greed, Adam took the name Lazarus and built a criminal empire, using the program to force Transformers to work for dictators and terrorists, helping them stomp out their enemies without casualties on their side. He even forced good guys like Bumblebee, Ratchet and Ironhide to work for killers. Sometimes, he would take "customers" on tours of his base, and would make the Transformers kneel to him to show his power over them. After three years of running this successful criminal empire, Lazarus had a group of Transformers slaughter an oil refinery in the Arctic as a demonstration to potential buyers, and casually began auctioning off all of them not long after.
- Transformers/G.I. Joe, by John Ney Rieber: Cobra Commander continues to prove himself capable of being an irredeemable psychopath when it comes to adaptations of his original iteration. With Cobra serving as a stand-in for the Nazi Party, Commander runs his empire with the same cruel egomania that the Nazis were known for. After discovering the Decepticons hidden in an ancient monastery whose inhabitants he has just had slaughtered, Commander forcefully takes control of the Decepticons and forces them to lay waste to numerous countries across Europe, including Berlin and Rome. Any survivors of these massacres, including the children, are forced into slave camps, and, later, used as human shields against the Commander's enemies. After forcing a Decepticon to exhaust all his energy in wantonly laying waste to enemies and allies alike, the Commander reveals his plan to use the Decepticons to institute a new world order under his rule where only the strong will survive and serve under his thumb. Cobra Commander is a megalomaniac whose status as a stand-in for the Nazi leadership makes him one of the most realistic, and wicked, baddies throughout the G.I. Joe franchise.
- IDW Generation 1 continuity
- Overlord, debuting as the Big Bad in Last Stand of the Wreckers, is without a doubt the most depraved Decepticon to ever grace Megatron's ranks. Though always a terrifying force of savagery, known and feared by friend and foe alike due to his psychotic brutality on the battlefield where he regularly slaughters dozens of enemies with his bare hands, Overlord's truly wicked nature comes out in full when he is sent to Garrus-9 to oversee the rescue of Decepticon prisoners. Deciding instead to take over the entire planet, Overlord executes the current Decepticon general, alongside any of his supporters, before turning the planet into a hellish concentration camp occupied by hundreds of Autobot prisoners. Overlord takes sick pleasure in the various atrocities he perpetrates against his defenseless prisoners, from dismemberment, to public executions, to "releasing" them, then chasing them across the planet in "hunts", all of which he subjects his own troops to should they annoy him. Having a pathological fear of defeat, Overlord's entire motive stems from always losing to Megatron in sparring matches, and to ensure he can't "lose" to the Wreckers when they come to rescue his prisoners, Overlord has all 50 of the surviving prisoners executed. Returning later in the More Than Meets the Eye story arc, Overlord escapes confinement and shreds his way through dozens of Autobots before Rewind sacrifices himself to take down Overlord, though not before Overlord rips all of his limbs off then bites his head in two, all of which he later taunts Rewind's spouse with. In his final appearance, Overlord once again oversees a horrifying war campaign against the Autobots, culminating in him ditching his allies to their fates when he grows bored of the proceedings. Overlord is an abomination of a Decepticon who horrifies and disgusts everyone he meets, his own teammates included, something he laughs about every chance he gets.
- More Than Meets the Eye:
- Pharma is a former Autobot Medic who went evil. After saving one of the main character's lives, he became the head medic at a medical facility on the planet Delphi. There he received death threats from an elite Decepticon unit who threatened to overrun the place, and began bribing them with organs, first from dead bots but later he began killing living ones. Eventually it becomes too much, and he has two other Decepticons unleash a plague on the facility to kill everyone and cover up his crimes. When he's revealed, he shoots a life-support, sending about 20 patients into near death states to distract everyone. He then tries to kill Ratchet twice before being thrown off the facility. He survives the fall and is recruited into the group of Chief Justice Tyrest, who drilled a hole in his head and is trying to destroy all Transformers he considers inferior; all the Decepticons admit to being freaked out by him. When he finds Ratchet again, he separates Ratchet's head and spark from his body and starts torturing him. To prove he is a better medic, he has one of his co-workers from Delphi, Ambulon, sliced in half, vertically from head to crotch, with a chainsaw, and tells Ratchet to fix him. Ambulon dies in agony before the chainsaw leaves him. Later Pharma shoots Brainstorm.
- Froid, originally a friendly rival of Rung's, destroyed their friendship when he plagiarized his work, and damaged his reputation. Later in his career, he assisted in the capture of a Serial Killer named Sunder, along with his accomplice and brother Spectre. However, while on a prison ship taking the brothers to Garrus 6, the brothers pulled a successful escape, with Froid as their hostage, though Spectre was killed as a result. After the escape, Froid offered Sunder a perverse offer: in return for Sunder serving as a subject for him to study, Froid would help him cope with the death of his brother and supply him with victims. After convincing Sunder he needed to see his victims in order to feed on them, Froid removed Sunder's eyes to inhibit his appetite. Held up on the planet Scarvix, Froid become rich and famous due to Sunder's abilities to read memories without a patient knowing, all while handing innocence Cybertonians to the madman. After coming across the Lost Light, Froid boarded the ship, looking for new victims for Sunder. After reuniting with Rung, he attempted to blackmail his one-time friend into giving him Rung's patient files. When Rung refused, he decided to feed him to Sunder, giving the Serial Killer his eyes as Skids to rushed in to warn Rung. In order to escape, Froid opened Sunder's cell, setting him free upon the Lost Light as he attempted to retreat.
- Shattered Glass: Ultra Magnus was locked up in his universe for trying to usurp Optimus Prime, getting his face ripped off in the process. He and several others travel to earth, where he assimilates numerous Autobots into the Junkion hordes, resulting in them becoming mindless slaves and dead in all but name. After that, he proceeds to set up a plan to take rarified energon from Earth with his sword and destroy it. His plan is foiled when a shield is placed around the Earth, but his real plan was to cause the death of the entire universe. Even the normal Decepticons turned against him, as they wanted to be the conquerors, and were appalled when they realized the extent of the damage.
- IDW Film Adaptations:
- Revenge of the Fallen: The Fallen himself is portrayed as even worse than his film counterpart. Once a member of the Thirteen Primes, The Fallen came to believe he was destined to become the most powerful of his brothers by re-powering the Allspark, then using it to make himself all-powerful. Using the Star Harvester, The Fallen drains the energy from a sun, uncaring that it leads to an entire planet dying, and blames it on one of his own servants when confronted about it. After attempting to use the Star Harvester once more, The Fallen comes to the realization that he no longer needs his Prime "brothers" or the Allspark, prompting instead to travel the universe searching for sentient life, then slaughtering countless worlds of their sentient species, absorbing the knowledge, weapons, and strategies of the billions he slays as he goes along. After butchering his Prime brothers, The Fallen attempts to use the Star Harvester to wipe out the entire Earth, taking extra time to crush humans underfoot while laughing. Though sealed away for thousands of years, The Fallen continues his wicked ways, as he reaches out and corrupts the noble Megatron into waging a war against Optimus Prime and the Autobots, leading to countless deaths and the destruction of Cybertron itself. The Fallen hopes to return to Earth and use the Star Harvester to destroy it for good this time, solely as a final act of spite toward his brothers.
- Dark of the Moon:
- Unlike in the film, Shockwave—also in the Foundation and Rising Storm prequel comics—is portrayed as a brutal and remorseless Decepticon assassin. Initially a follower of Sentinel Prime, Shockwave expressed disgruntlement with an age of peace and freedom and, as part of Megatron's Defense Force, eagerly massacred dissenting Cybertronians. After joining the Decepticons, Shockwave earned a reputation as Megatron's most lethal subordinate, openly admitting to enjoying the sounds of Autobots dying. Left in command of the Decepticons on Cybertron whilst Starscream searched for the Allspark, Shockwave waged a brutal campaign against the remaining Autobots, killing, amongst others, the Autobot Chromia. On Earth, Shockwave murders the Autobots Longarm and Salvage, as well as the entire crew of an oil processing plant, without provocation. Enslaving the drone who would later become "Brains" to build a "cage" for his Driller, Shockwave openly plans to terminate him when he is no longer useful. When Brains escapes, Shockwave tracks down Starscream's Decepticon splinter group, casually killing Deadlift simply for being in his way, and conscripts them into tracking Brains down. Shockwave then goes on a killing spree in the NEST base in Diego Garcia, killing all the personnel, human and Autobot alike, including traumatized Autobot refugees. Devoid of empathy, Shockwave mocks Elita-One's death at his hand to Prime's face and, later, sadistically taunts Prime about the Autobots that Shockwave killed during their encounter in Chernobyl. Even the death of the Driller, his loyal pet, fails to rouse any emotion from Shockwave, who treats its death as an inconvenience. A merciless sadist who revels in killing, Shockwave terrifies Autobot and Decepticon alike.
- Dylan Gould, unlike in the film, is portrayed as a sadistic psychopath with delusions of grandeur. Having willingly allied with Decepticons years back, Gould covers up the Decepticons' plans and presence from the public eye, having anyone who attempts to learn the truth murdered by his personal Decepticon attack dog, Laserbeak. Once the Decepticons reveal themselves and attack the Earth, Gould uses Sam Witwicky to spy on the Autobots under threat of slaughtering his girlfriend, Carly, and giddily gives the order for the Autobots to be shot down while they are attempting to leave the Earth. Masterminding the invasion of Chicago, Gould has the Decepticons kill countless people and destroy much of the city while turning it into a fortress. Gould ultimately plans to assist the Decepticons in transporting as much of humanity to Cybertron as possible, then use them as slaves to rebuild Cybertron while Gould lords over them as their master. Even when the Autobots and humans begin defeating the Decepticons, Gould still activates the portal to bring Cybertron to Earth, completely eliminating any possible claims he had to not being fully complicit in the Decepticons' actions. Always wearing a smile and having a witty quip on hand to cover up his raving egomania, Gould truly represents the very worst humans have to offer.
- Revenge of the Fallen: The Fallen, also known as Megatronus Prime, is this film's Big Bad and the film universe's first Decepticon. Originally one of the 7 members of the Dynasty of Primes, The Fallen betrayed his brothers and attempted to use the Star Harvester on Earth's Sun regardless of the Dynasty's code against taking life, solely because of his Fantastic Racism towards primitive humankind. Eons after his defeat, The Fallen corrupts Megatron, creates the Decepticons, and orders him to find the All Spark, making him responsible for the events of the first film. After he lures Optimus Prime to his death using Sam as bait, The Fallen sank an aircraft carrier, attacked several human cities, and slaughtered a sizable military force while acquiring the Matrix of Leadership to activate the Star Harvester again, fully intending to wipe out the human race.
- Age of Extinction: CIA agent Harold Attinger is the creator of "Cemetery Wind," a black-ops group taking it upon itself to wipe out all Transformers upon the planet regardless of faction, all out of nothing more than Attinger's Fantastic Racism. Attinger entered a deal between himself, Lockdown, and Joshua Joyce's Kinetic Solutions Incorporated where Lockdown gives the remains of any Transformer he murders to Joyce for production into man-made Transformers, and Attinger would trade Optimus for the Seed needed to create more man-made Transformers to sell to the US Army. At first, Attinger may come across as well-intentioned, but given that he worked with Lockdown, wanted to create Transformers of his own, would have millions of innocents killed by The Seed, along with his own attempts to kill any humans who could get in his way-such as Tessa Yeager by proxy of his Dragon Savoy and Cade Yeager at his own hand—and ordering Savoy to murder witnesses of his presence in Hong Kong, it is clear Attinger is a hypocrite, if not merely a Straw Hypocrite, out to get rich.
- Bumblebee: Shatter and Dropkick are a pair of Decepticons out to hunt down and kill Optimus Prime. Introduced torturing and murdering the Autobot Cliffjumper, the two arrive on earth where Dropkick kills a human simply for fun. Directed to the human authorities, the two claim to be peacekeepers hunting down a criminal to give them access to humanity's satellites. After capturing and torturing Bumblebee, the two murder a doctor who was helping them, revealing their intent to bring their forces down on Earth and kill every human being, not stopping until the planet is a cinder. A vicious pair of Brains and Brawn, Shatter and Dropick embody the worst of the Decepticons.
- Dark of the Moon: In the novelization by Peter David, Sentinel Prime loses all of his film counterpart's redeeming features, turning the somewhat-sympathetic Well-Intentioned Extremist into a psychopathic Knight Templar. Having made a deal with Megatron eons ago to betray his allies the Autobots, Sentinel fulfills this deal in the present after pretending to assist the Autobots, showing his true colors by ruthlessly executing three of his "brothers." Sentinel steals the Pillars from the military group NEST by threatening its director, Charlotte Mearing, stating that if she doesn't give him the Pillars, he will force her to watch as he slaughters every man, woman, and child he can until she does. Lying to humanity to get them to force the Autobots to leave Earth in exchange for Sentinel's offer of peace, Sentinel goes back on his word, orchestrating a full-scale invasion of Earth by the Decepticons and personally overseeing the blood-soaked conflict in Chicago. Sentinel ultimately plans to transport as many humans to Cybertron as possible, then torture and abuse them into reconstructing Cybertron, leaving the rest of humankind to be destroyed alongside the Earth by Cybertron's gravitational field. In the end, Sentinel treats the deaths of Autobot and Decepticon alike with cold satisfaction, proclaiming that he will be the only god left on Cybertron when the dust settles, proving once and for all that, despite his claims of wanting the best for his people, Sentinel truly only cares for himself and his supposed claim to godhood.
- The Game (DS): Megatron lacks his film counterpart's nobler traits and replaces it with raw brutality. Having plunged Cybertron into civil war after killing his own father, Megatron tore out Bumblebee's vocal processor when he launched the Allspark into space. He followed the Allspark to Earth, but wound up frozen in the Arctic Circle. After being thawed out by his followers, Megatron's murderous rage was only tempered when they planned to blow up Hoover Dam and drown thousands of people. In Autobots, Megatron used the Allspark to terrorize the city of Tranquility and mortally wounded Create-A-Bot while trying to kill his own brother, Optimus Prime. In Decepticons, he tracked down and murdered Jazz after he foiled his plot to destroy Hoover Dam. After terrorizing Tranquility, Megatron killed Optimus and hunted down his traitorous lieutenant Starscream. Create-A-Con was gravely wounded after helping him defeat Starscream, and Megatron chose to kill him rather than waste resources trying to repair him. Megatron showed no remorse for the Decepticons who gave their lives for him and believed that the weak were only meant to serve the strong.
- War for Cybertron & Fall of Cybertron: Megatron, leader of the Decepticons, is the instigator of the first game's titular war. A merciless tyrant, Megatron is bent on the conquest of Cybertron and the destruction of the Autobots, with the resulting war ravaging Cybertron and devastating its population. After taking control of the powerful Dark Energon, Megatron infects Cybertron's core with the substance, further damaging the planet and bringing it under his control. When this corruption is cleared away, the core is forced to shut down, leaving Cybertron on the brink of death. As the Autobots try to leave the dying world, Megatron has their ships shot down, endangering the future of his own species to satisfy his hatred for the Autobots, before sending the monstrous Trypticon after them. In Rise of the Dark Spark, Megatron acquires the Dark Spark and uses it to resurrect dead Autobots as mindless drones who will fight on his side. When offered a truce by Optimus Prime in Fall of Cybertron, Megatron refuses, blaming Optimus for Cybertron's decline, declaring himself the planet's future, and trying to destroy the Autobots' last hope of leaving Cybertron alive. After discovering the damaged Trypticon, Megatron, not caring if Trypticon is still conscious or not, has him forcibly converted into a warship for his own use. As the Autobots flee Cybertron, Megatron stages one last assault on the Ark, doing his best to kill Optimus Prime and doom the Autobots. Ruthless and bloodthirsty beyond measure, Megatron is willing to doom his own homeworld and his entire species to satisfy his lust for power and hatred for his enemies.
- Rise of the Dark Spark: Lockdown is a bounty hunter searching for the titular Dark Spark. After discovering that it has landed on Earth, he and his army of mercenaries attack a city in their quest to find it, and also torture Drift and nearly kill him and Bumblebee after they interfere. Once he acquires the Spark, Lockdown and his army later attack a second city so he will gain access to a time bridge hidden underground. As he prepares to activate the bridge, he gloats to Optimus Prime about how he plans on using the bridge to bring the Decepticons down to Earth, which would reignite another Cybertronian civil war that would result in the Earth being destroyed. Relishing in his profession, Lockdown nearly started another galactic war that would've killed millions of humans and Cybertronians alike, all so he could satisfy his greed.