Skeletor is the main antagonist of the Masters of the Universe franchise, and is the most dangerous threat on Eternia. His only goal is power, and to that end, he will not rest until he possesses the secrets of Castle Grayskull, which will enable him to become master of the universe. This places him in direct conflict with the only man powerful enough to stop him, He-Man.
Skeletor was initially presented simply as an evil demon from another dimension, and in general, his origins were not as important as his evil motives. However, the introduction of Hordak as Skeletor's former teacher provided a brief glimpse into a past. Near the end of the original Masters of the Universe franchise. It was hinted that Skeletor might have once been Keldor, the brother of He-Man's father, King Randor. The development of Skeletor's backstory as a dashing, ambitious villain played heavily into his characterization in the 2002 relaunch of the franchise.
Skeletor was one of only a handful of characters that carried over to The New Adventures of He-Man brand. In this, He-Man was sent to the far future to help the Galactic Guardians save the last of humanity from the Evil Mutants. Skeletor follows his enemy and offers his services to the Mutants simply because he must rid the universe of He-Man.
- Main article: Skeletor (early minicomics)
Skeletor was originally an inhabitant of another dimension, populated with others of his kind. During "the great wars", a dimensional hole opened up and Skeletor was thrown from his home dimension to Eternia. Skeletor initially sought to open a portal back to his homeworld, which would allow his people to invade and conquer Eternia alongside him, before he became more interested in simply seizing the power of Castle Grayskull for himself.
In later Minicomics, which largely ignored Skeletor's original origin and took more cues from the animated series, Skeletor was hinted to be the long lost brother of King Randor, Keldor, who was said to have disappeared many years ago when he was lost in another dimension. Skeletor was determined that no one should learn the secret of Keldor, as the truth would lead to his destruction. Skeletor was also forced to contend with the return of his old mentor, Hordak, and forged an uneasy alliance with King Hiss.
DC Comic Books (1982)
- Main article: Skeletor (DC Comics)
In the stories written by Paul Kupperberg for DC Comics, Skeletor was presented much the same way as he was in the early Mini-comics. He sometimes refers to himself as "The Dark Lord". Skeletor was already in possession of one half of the Power Sword and managed to find the second half when Mer-Man lead him through an underwater dimensional portal on Eternia's ocean floor to locate the missing half of the Power Sword on Earth.
Golden Books (1985)
In the Golden Books Hardcover book The Horde Skeletor was a native of Etheria. When Hordak's horde took over Etheria, Skeletor willingly became Hordak's student. Together, they learned how to master the usage of the most powerful mineral in the universe,
Skeletor was too young to master the power of Etheramite, but tried to use it anyway, leaving his face with its skeletal appearance. He took some of Hordak's Etheramite and left Etheria, looking for his own world to rule. Skeletor eventually came to Eternia and established himself at Snake Mountain. Years later, he finally mastered the usage of Etheramite and increased his power, planning to take over both Eternia and Etheria. However, his usage of Etheramite revealed his location to his former mentor Hordak, who came to Eternia to punish him for his betrayal.
- Main article: Skeletor (Filmation)
Skeletor was described by the Sorceress of Castle Grayskull as a demon from another dimension. He was a pitiless villain who commanded an army of warriors from his headquarters in Snake Mountain. Skeletor's past was shrouded in mystery, but it was revealed that had once been a member of the Evil Horde and studied under Hordak, becoming his favorite pupil. When Hordak and the Horde invaded Eternia, Hordak attempted to kidnap the kids of King Randor and Queen Marlena, and when their attempt went awry, he abandoned Skeletor, who, seeking revenge, double-crossed the location of the Horde's secret base at Snake Mountain.
With Hordak having left Eternia for another world, Skeletor set himself up in Snake Mountain and recruited his own army of henchmen, seeking to conquer Eternia and capture Castle Grayskull. Skeletor became the arch-enemy of He-Man and concocted various schemes to eliminate him. Later, he would be reunited with his old mentor, Hordak, and also made an enemy of He-Man's sister, She-Ra.
1987 live-action film
- Main article: Skeletor (1987 Movie)
In the live-action 'Masters of the Universe (1987 film), Skeletor again was the primary antagonist and was depicted as a far more competent, serious-minded, and baleful character.
Skeletor was clad in regal, black robes and carried an ornate, metallic staff. Skeletor used a device called the Cosmic Key to launch a surprise attack on Castle Grayskull, achieving a sweeping victory and managing to capture The Sorceress. Though He-Man managed to evade capture, Skeletor eventually tracked his old enemy to Earth and returned him to Grayskull in chains.
Skeletor ultimately managed to obtain the power of Grayskull for himself, transforming into a golden, God-like form. Although apparently defeated by He-Man, Skeletor would emerge from a pit at the bottom of Grayskull and swear he would be back.
The New Adventures of He-Man
- Main article: Skeletor (New Adventures)
Along with He-Man and The Sorceress, Skeletor was one of only a handful of characters who appeared in the He-Man (toyline) and its accompanying media, such as The New Adventures of He-Man (cartoon). Skeletor was seen donning a new costume including an armored chest plate, cybernetic implants, and a cape and helmet. His Havoc Staff was replaced by the Skull Staff. In the Mini-Comics which came packaged with the toyline, Skeletor was forced to undergo cybernetic enhancements after he was gravely injured after witnessing He-Man's transformation.
Skeletor traveled to the future, joining forces with the Evil Mutants of Denebria and their leader, Flogg. He-Man also journeyed to the future, becoming an ally of the Galactic Guardians and the defender of the peaceful planet of Primus, transporting the eternal battle between the two enemies to a new location in the depths of space.
The animated series saw Skeletor go through several different looks throughout the series, updating his armor to coincide with the different action figure variants in the toyline. He was voiced by Campbell Lane. This version of Skeletor was a much more intelligent and manipulative character, with a sardonic sense of humor. At the end of the series, he engaged in a final battle with He-Man, who trapped him within a Shuttle Pod and exiled him into the far reaches of space.
2002 TV series
- Main article: Skeletor (2002)
In the 2002 revival of the franchise and its accompanying animated series, He-Man and the Masters of the Universe (2002), Skeletor was revealed to have once been Keldor, a warlord who trained under Hordak. He gathered a small band of warriors to attack the Hall of Wisdom, where they encountered resistance from Captain Randor and his officers. Keldor engaged Randor in a duel, where he was ultimately disarmed. Not willing to accept defeat, Keldor produced a hidden vial of acid from within his armor and hurled it at Randor, who blocked the impact at the last moment, causing the acid to splash back into Keldor's face.
Keldor was saved at the last moment by Hordak, who transformed his melting face into that of a floating Skull. Skeletor and his followers were imprisoned in the dark hemisphere behind a Mystic Wall for many years until Skeletor eventually brought it down with a device of his own creation. Skeletor quickly returned for revenge on the now King Randor, and sought out the Council of Elders, only to find they had disappeared. He soon made an enemy of He-Man and set his sights on the seemingly innocuous Castle Grayskull, believing, correctly, that that was where the Elders' power now resided.
DC Comics (2012)
- Main article: Skeletor (New 52)
Skeletor was initially the heir to the throne of Eternia, but his father King Miro decided to make Randor king instead, because Keldor was a half-blood, his blood mixed with a Gar. Miro favored Randor over Keldor, causing Keldor to grow bitter over time. Keldor eventually came to serve as Randor's advisor, but sought to overthrow his brother and take the throne that he rightfully believed was his. While on the verge of death thanks to a curse, Keldor stabbed Randor and used his blood to become Skeletor, with the aid of his mentor, Hordak.
Masters of the Universe Revelation
- Main article: Skeletor (Revelation)
- Main article: Skeletor (Netflix)
Powers and abilities
Skeletor possesses an array of mystic powers that seem to vary depending on the whims of the particular writer using him at the time, however, all portray him as an extremely powerful sorcerer with control over a vast range of dark magical powers. He also possesses the considerable scientific skill and is shown to have skill in creating various machines and devices in the Filmation and New Adventures animated series. A notable skill present in the Filmation series was Skeletor's ability to instantly transport himself back to Snake Mountain, usually by saying "I'm going back to Snake Mountain".
He is usually armed with a magical weapon called the Havoc Staff; a long pole crowned with a small replica of a ram's skull and a crystal ball embedded within. He can discharge bolts of mystic force from the head of the staff, or use it as a focus for more powerful forms of magic. Sometimes Skeletor displays the ability to discharge energy from his own body, as seen in the 1987 film where he casts lightning from his hands, and in the original animated series where he projects energy from his fingertips and even his eye sockets. In the 2002 series, his innate powers seem much more limited; though his abilities, when in conjunction with his Havoc Staff seem nearly unlimited in scope and highly potent in raw power.
In the early mini-comics, Skeletor sometimes possesses one-half of the Power Sword. From this weapon, he could also project magical energies. He also displays many other skills, such as the ability to teleport himself and others over vast distances, send telepathic commands to his minions, open gateways between dimensions or perform remote viewing. He has also shown himself to be a gifted swordsman. As a master of the mystic arts, he is also privy to much secret knowledge about the universe.
Though mainly a sorcerer, Skeletor is more than capable of physical combat, and has above average physical strength, as proven in numerous encounters with He-Man.
In the 1983 series, Skeletor was voiced by veteran voice actor Alan Oppenheimer, who gave the character a high-pitched, demonic voice. Though initially presented as a solemn and chilling villain, later episodes of the series would present the character in a more comedic light.
Skeletor was voiced in the 2002 series by Brian Dobson. During an interview with fans on He-Man.org in 2005, series producer Ian Ritcher revealed that, had the series continued, Keldor would have been revealed as the brother of Randor. 
In Masters of the Universe: Revelation, he is voiced by Mark Hamill.
Masters of the Universe Classics toyline (2008)
The Masters of the Universe Classics toyline's packaging featured short character biographies that merged various elements from across the many different incarnations of the franchise, as well as newly developed information, to form a distinct new "Classics" continuity. Over the course of 11+ years, Skeletor's story went through several twists and turns.
Skeletor, once known as Keldor, the half-brother of Captain Randor, was mortally wounded in battle with his brother and turned to Hordak to save his life. Hordak merged Keldor with the extra-dimensional being Demo-Man (originally, the planned name for the Skeletor character) from Despondos. Keldor was forever changed into Skeletor, Overlord of Evil. He gathered together the greatest outcasts and evil warriors of Eternia in his quest to gain entry into Castle Grayskull and obtain what he believes is the universe’s ultimate power source.
Subsequent Classics bios and minicomics explore Skeletor's various transformations into his variant forms, the revelation that he and Evil-Lyn had a son, Skeletor's subsequent death, his return as a zombie, his true resurrection to life and return to his Keldor form, his choice to willingly turn himself back into Skeletor, and his ultimate plan to become a god, which was foiled by his nemesis, He-Man.== Toys==
Masters of the Universe (1981)
1981 Skeletor: Skeletor was the second toy ever made for Masters of the Universe, immediately following He-Man. He was released in 1981 in the first wave of Masters of the Universe toys. Skeletor came with his signature Havoc Staff and with one half of the Power Sword, which could be combined with another half held by He-Man and used to open up Castle Grayskull.
Masters of the Universe: Origins
Origins Skeletor: In 2020, as part of the Masters of the Universe: Origins toyline, a Skeletor toy modeled after the original 1982 toy was released. Origins Skeletor comes with the Havoc Staff and half of the Power Sword, mimicking the original toys gimmick.