Complete Monster/Godzilla

If Godzilla is "king of the monsters", then it's scary to imagine how bad his enemies must be. These ones here are among the very worst.

Films

 * The majority of Godzilla's enemies are simply big, dumb and/or mind controlled. A few, however, belong on this list, with King Ghidorah being the standout. One of Godzilla's most powerful adversaries, Ghidorah is one of the few monsters to actively enjoy causing destruction, as evidenced by his cackling, Joker-esque laugh. An Omnicidal Maniac of the first order, Ghidorah has made a career out of destroying planets and all the life on them, and seems to get a thrill out of taunting the human military when it fails to destroy him. His Expy, Desghidorah, took it up a notch by slowly draining the Earth of all life.
 * And there's his evolved form, Kaiser Ghidorah/Monster X. Originally mind-controlled by the Xillians in his Monster X form, Ghidorah battles Godzilla to a standstill, during which time the aliens are defeated. Freed of their control, Ghidorah evolves into Kaiser Ghidorah and proceeds to use it's Vampiric Draining on Godzilla, slowly torturing him to death for no real reason beyond hatred (since it's no longer receiving orders from the Xillians).
 * This isn't a first for Ghidorah. In Destroy All Monsters, after the Kilaaks' control tower was destroyed, freeing all the creatures under its control, King Ghidorah kept right on attacking Godzilla and co. And that's without getting into the Rebirth of Mothra films, where Grand King Ghidorah drained the souls of children. It's about as malevolent as a film monster can get.
 * Gigan is of a similar mind to Ghidorah. Essentially a forty-story Psycho for Hire, Gigan enjoys nothing more than slowly dismembering other monsters with his buzzsaws and scythes. He regularly attacks Earth while in the employ/thrall of one alien race after another, and typically takes his time in slowly cutting his opposition to pieces - even when he could just shoot them. He's also a huge Dirty Coward, frequently abandoning his allies whenever a fight doesn't go his way, and enjoys ganging up on single opponents alongside the likes of Megalon and fellow sociopath Ghidorah. Amongst the fandom, he is generally regarded as Godzilla's most brutal adversary.
 * Destroyah from Godzilla vs. Destroyah:. To give a good idea as to how sadistic he is, he BRUTALLY murders Godzilla Junior in front of Godzilla himself and, just to rub the proverbial salt into the wound, then wraps his tail around Godzilla's throat and begins to drag him around while laughing. While Godzilla mourned the loss of his only child, Destroyah grabbed him and hurled him away, preventing him from attempting to revive him or grieve. The fact that Destroyah seemed to be enjoying every minute of it hammers home how twisted this monster is.
 * Controller X from Godzilla: Final Wars. The Xillian Commander simply wanted to take Earth peacefully and was a Well-Intentioned Extremist trying to save his people. Controller X assassinates him the moment he gets the chance and takes over, instantly letting loose his entire army of monsters and beginning the systematic destruction of human civilization. While many alien invaders in Godzilla movies have done just that, it's the sadistic glee present in Controller X as he watches the horror he's unleashed that makes it clear that, unlike his more peaceful predecessor, he's a sadist who enjoys what he's doing. When he captures the Gotengo at the climax of the film, he orders his men to slaughter the entire crew except for the ones he wanted to kill personally. Whereas his predecessor took prisoners even when he could've simply let them die, X has absolutely no regard for life at all. During the Final Battle of the film, he takes his time to enjoy the Curb Stomp Battle he's inflicting on his opponent.
 * Spacegodzilla, an Evil Twin of Godzilla created when Godzilla's cells fused with a crystal alien. Appearing in Godzilla VS Spacegodzilla, the corrupted clone only had two focuses: Take Over the World and slaughter the members of inferior species, his genetic donor included. After thoroughly butchering the inhabitants of a space station that he flew past, Spacegodzilla assaulted Monster Island and kidnapped Godzilla's adoptive son, Godzilla Junior, purely out of spite for his original template. He then converted an entire city into a fortress made out of giant crystal spires that drained all life from the Earth and transferred it into him, enabling him to become more powerful. Fortunately, he was slain by Godzilla and MOGUERA before he could repeat the process in other cities. Space Godzilla was described by Mothra's priestesses as an abomination, and, seeing as he was as deliberately malevolent as a Heisei monster could get, that's a very accurate assessment.
 * Clark Nelson of Mothra is an immoral businessman whose focus is solely on making money. He has his men gun down villagers so that he can abduct the twin fairies that were in their protection, all so he can exploit their powers as shows for making more quick bucks. He also sends his men to kill the protagonists and flees from the country when Mothra begins his rampage, gunning down a policeman along the way! But his most vile action is torturing a child who was trying to rescue the fairies, without any second thoughts about it whatsoever.
 * Chuck Wilson, the leader of the Futurians, was paranoid about Japan becoming an economic superpower, and so hatches a mad plan to ensure this never happens. He steals a time machine and then takes three genetically engineered creatures called Dorats with him to the past. Convincing Japan's government to aid him with lies about Godzilla, he has his lackeys travel to the past and attempt to erase Godzilla from history. When they fail, Emi Kano, on Wilson's orders, leaves the three Dorats behind, where they are hit by a nuclear explosion, absorbing the radiation and becoming forcibly fused together into King Ghidorah. In the present, Wilson takes control of King Ghidorah and directs it like a living WMD. It destroys an entire city and kills hundreds of people under his orders, before flying to Hokkaido next, destroying everything in its path. Eventually, Japan has no choice but to bring Godzilla back, making Wilson indirectly responsible for all the evil Godzilla does in future movies. Wilson, showing no remorse for all the lives he's taken, just gloats that either Ghidorah will destroy Japan, or Godzilla will do it for him.
 * Mulu-elu Galu-gu is a Bilusaludo who, exploiting Earth's desire for a weapon to combat Godzilla, created Mechagodzilla, intending to turn it against humanity once it disposes of Godzilla. However, he was forced to leave Earth before he can enact upon that plan, leaving Mechagodzilla unchecked as it kills off numerous lifeforms still living on Earth, humans included. Finding Mechagodzilla once more, Mulu-elu tricks Haruo Sakaki and his soldiers into injecting themselves with Mechagodzilla's nanometal in an attempt to defeat Godzilla. When they learn of Mulu-elu's plans to assimilate the entire Earth in nanometal afterwards, killing all life in the process, Mulu-elu uses the nanometal to kill most of Haruo's men whilst leaving Haruo's Love Interest, Yuko Tani, in an irreversible coma. Proud of being called a monster for his self-appointed superiority and omnicidal designs, Mulu-elu Galu-gu was the most evil being in a world full of monsters.

Comics

 * The comic Godzilla: Gangsters And Goliaths gave us Ryoto Takahashi, Yakuza boss and all-around bastard. He murders Detective Sato's partner in cold blood and has Sato dumped on Monster Island, intending that he die far from his home and family, and also planning to frame him for the murder of his own partner. So when Sato returns home with the Elias and Mothra, Takahashi kidnaps the Elias, which leads to most of Monster Island's population, Godzilla included, rampaging through Tokyo. After slaughtering the priests of Mothra who came to retrieve the Elias, Takahashi demands that the Prime Minister pay him millions of dollars, or he will simply let Tokyo burn to the ground. But even once his demands have been met, he refuses to end the destruction and even attempts to kill his own henchmen who say that he should! To top it off, he does this out of insistence that he, not Godzilla, go down in history as Japan's greatest monster. He came close to getting his wish, but received competition from this next guy...
 * Dr. Deverich from the comic Godzilla: The Half Century War is quite possibly the worst human being in the entire franchise. After abandoning the members of the Anti-Megalosaur Force (AMF) when they refused to utilize his designs, Deverich sold his psionic transmitters on the black market, which enabled terrorists to summon kaiju monsters to any city they chose to target. When testing his first device on Godzilla and Anguirus, he ended up leveling Hanoi and much of Vietnam without any remorse at all. He then went on to obliterate the city of Accra, Ghana, so that every kaiju monster on Earth could arrive there as part of a demonstration to his customers. After perfecting his design in 1987, he used it to reach out into space and summon Space Godzilla to Bombay, annihilating it as well. The same transmitter also accidentally called Gigan and King Ghidorah to Earth, resulting in the near extinction of the human race! With a criminal career spanning decades and a death toll in the billions, Dr. Deverich outdoes every kaiju in the series when it comes to monstrosity.
 * Godzilla: Rulers of Earth: Emperor Karkaro of the Cryog likes to present himself as a great warrior for his people, but in truth sacrificed them and his entire world to save his own skin when King Ghidorah attacked. Later arriving on Earth when his former commander Rhizon has been trying to conquer it, Karkaro seizes control of the invasion and deploys the monstrous Trilopods to devastate Earth's cities and kill countless people before having them try to drain the energy of Earth's Kaiju. Psychologically tormenting Rhizon, Karkaro has him imprisoned while vowing a torturous death when Rhizon calls him out for his cowardice and has Rhizon's innocent crew executed out of spite. Karkaro vows to wipe out all life on Earth and raze everything on the planet to ash solely to take it for himself and salve his ego, showing himself to be the worst of all the aliens who threatened Earth.