Skeletor, the sworn enemy of He-Man and the Masters of the Universe, is one of the most recognizeable villains in pop culture. After all, it's hard to forget a ripped, blue-skinned guy in a purple gladiator costume with a skull for a face. Not to mention that nasally voice. But, for years, the backstory of Eternia's most prominent threat was shrouded in a purple hood of mystery. What creature was Skeletor meant to be? Was he once human? Are there more characters that look like him? How did he get that skeletal mug? And what -- other than a baseless need for power -- is driving him?

The miniseries of comics produced with the 1981-3 Masters of the Universe toyline from Mattel were pretty sketchy in providing any answers, preferring to focus on Skeletor's present-day quest to get a hold of Castle Grayskull's power than his origins. They did, however, reveal that Skeletor was in fact an interdimensional invader thrown into Eternia. The Filmation animated series then threw out this idea in favor of one involving some Eternian royal family drama instead, which was fleshed out further in the accompanying comics, as well as DC's Masters of the Universe "Origins" one-shots. (Skeletor's was released appropriately on Halloween 2012.) While we may finally know the full details of Skeletor's origins, there's still a surprising amount left unspoken about his physiology.

20 IT'S UNKNOWN WHETHER HE HAS A NECK

Skeletor

We're used to villains having the odd limb missing, but a neck is a pretty significant body part to not know the whereabouts of. Because of the way Skeletor's hood darkens the area between his head and shoulders -- and is rarely down -- the Filmation series never provided a proper answer as to whether anything connects the two. The few times his hood was pulled down, it was conveniently never far enough to reveal anything.

Later iterations have been confusingly inconsistent in their explanations. The New Adventures of He-Man sequel series created a physical connection between head and body at the back, while the 2002 reboot series implied that his skull magically floats above his fleshy body. Really, the only thing we know for sure is that he definitely did have a neck once but, currently, his relationship status with it is: "It's complicated."

19 HIS LOOK WAS INSPIRED BY A REAL CORPSE

Skeletor

It's hard to imagine that a figure as fantastical-looking as Skeletor could have any real-life inspiration. But, as we learnt from Mattel concept artist and designer, Mark Taylor in Netflix's The Toys That Made Us docu-series, Skeletor's roots are more grounded than you'd think. In the episode telling the story of how He-Man came to be, Taylor said Skeletor's design drew from a place of real fear.

At Pike Amusement Park as a child, the artist encountered what he thought was a real dead body -- an experience that haunted him into adulthood. It wasn't until decades later while watching the Discovery Channel that he discovered his suspicion had been correct. The body was real. And, it had a great backstory: a robber who'd been killed in a gunfight with the police in 1911.

18 HIS FACE WAS BURNED OFF BY ACID

Skeletor

Over the years, there have been a couple of different explanations as to how Skeletor's skull parted ways with its flesh -- all of them as gruesome as you'd expect. In the revival series in the early '00s, Skeletor's origins touched upon by the original series were expanded upon. Skeletor was formerly known as the traitorous warlord, Keldor.

Keldor was the student of Hordak, leader of the Evil Horde, and ended up staging a coup against the then-Captain Randor in the Hall of Wisdom. Randor and his troops fought back, and he and Keldor became locked in a one-on-one confrontation that saw them equally matched. Keldor played dirty, lobbing a vial of acid at his enemy who deflected it back, corroding away the blue skin of Keldor's face.

17 HE'S HALF HUMAN

Skeletor

Though he doesn't look it, Skeletor is actually human. Well, half of him is, anyway. Keldor, as he was formerly known pre-skull head, is half-human and half-Gar. "Gar" is a race of humanoid, blue-skinned people native to Eternia -- which explains the unusual color of Skeletor's skin. Skeletor might just be the only one of his kind, too -- though fans have their doubts about that.

And in fact, it's not just Skeletor's skin that's blue -- it's his blood, too. Keldor is King Randor's half-brother, making him He-Man's uncle. In the recent DC comics He-Man series, the Gar were revealed to have once been loyal allies to King Grayskull, even fighting alongside humans to defeat the evil Hordak. That was until the Council of Elders' Gar Adi heard a prophecy predicting the King's descendant would bring about doom and assassinated Grayskull, breaking the alliance.

16 SOMETIMES HE HAS HAIR

Skeletor

The only thing creepier than a reanimated skull is a reanimated skull with straggly bits of hair. That's how The New Adventures of He-Man cartoon chose to reinvent Skeletor in 1990 (along with some other major physiological differences we'll get it into later.) Sure, it makes an already menacing character appear even more frightening but, it also just looks super gross.

Skeletor's do -- or what was left it -- was revealed when his helmet is destroyed in the episode, "The Tornadoes of Zil," one of very few times the villain has been without something covering his head. In this continuity, locks of dark hair still cling to the back of his skull as remnants of his former self. This hairy look was also incorporated into the Skeletor "Battle Blades" tie-in toy.

15 HIS SKULL HEAD IS THE RESULT OF A CURSE

Skeletor

Another reason given for Skeletor's distinctive bony head is a lot more mystical than just a backfired attempt to win a duel. In DC's Master of the Universe: The Origin of Skeletor one-shot, writer Joshua Hale Fialkov and artist Fraser Irving dived into the Lord of Destruction's dark beginning deeper than ever before. Much of the elements from previous incarnations remained the same.

Skeletor was once Keldor, brother to Randor and son of King Miro. Frustrated that his half-breed status meant he would always be second best to his brother, Keldor aligns himself with Hordak, but after Randor is kidnapped by Hordak's henchman, Keldor desperately searches for him until his body and mind begin to weaken. Death itself approaches to claim Keldor but he defeats the spectre, keeping his life but cursing his flesh to rot away.

14 HE WAS DRIVEN MAD BY BEING A HALF-BREED

Skeletor

DC's Origin of Skeletor comic not only retconned the loss of Skeletor's original face in a darkly magical way, but it added even more twisted layers to his character. The relationship between Keldor -- Skeletor's former identity -- and his brother, Randor, the future king of Eternia, became the key to Keldor's descent into villainy. Being half-human and half-Gar ensured that Keldor, despite being King Miro's eldest son, would never be his heir.

Keldor's bitterness led him to become Hordak's apprentice, who only fed his indignation that his blood wasn't good enough for the throne. After being separated from his brother, Keldor reunited with him a cursed man -- his face and mind eaten away. Keldor -- convinced his brother's blood held his salvation -- pulled a knife on Randor, and crossed into Hordak's domain. Hordak rewarded his apprentice by rebirthing him as Skeletor.

13 HE MIGHT BE A LICH

Lich Dungeons & Dragons

Keldor was the half-human, half-Gar son of Eternian King Miro, and brother to Randor. But, what is Skeletor? A chattering skull that may or may not be magically floating above a fleshy body? Reborn from the brink of death? That doesn't sound like a normal, living being. You could just chalk it up to the nature of Skeletor's cursed existence if you go by the 2012 DC Comics explanation, but some fans have speculated that Skeletor may qualify as a lich.

In old English, "lich" literally means "corpse." In fiction, liches are the byproduct of someone messing around with the laws of nature using demonic or necrotic sorcery -- namely to try and cheat death -- and becoming undead themselves. You can clock a lich by their skeletal appearance and powerful magic, and, taking the newer He-Man continuities into account, Skeletor definitely ticks most of the boxes.

12 HE CAN SHOOT LIGHTNING AND ENERGY BEAMS

Skeletor

The guy who proclaims himself to be the "true" ruler of Eternia definitely has enough qualifications for the position. Skeletor is not only a master magician but he's kind of the evil version of Thomas Edison, able to engineer all sorts of weird mechanical devices and weapons to help with his schemes. If that weren't enough, Skeletor has displayed impressive offensive powers stemming from his body, too.

As well as his Havoc Staff, his animated versions can shoot energy beams from the tips of his fingers and his eye sockets. The live-action 1987 movie took this idea one step further, giving the villain the ability to shoot lightning from his hands. Return of the Jedi had come out just five years prior to this, so it's not hard to imagine that the filmmakers may have been influenced by the Emperor's Sith powers.

11 HE USED TO BE AN INTERDIMENSIONAL DEMON

Skeletor

The comics miniseries that came with the original line of Masters of the Universe toys in 1982 painted quite a different picture of the Eternia we got to know in the subsequent cartoons. For starters, there was no Prince Adam, only a jungle-dwelling He-Man leading his barbarian tribe. Skeletor was also not a native Eternian, in fact, he was from way out of town.

He ended up in He-Man's world by accident after being thrown from his own dimension through a portal that sealed behind him. His motivation for seeking the power of Castle Grayskull was to reopen that portal and allow the rest of "his kind" to invade Eternia. Members of that army seemed to be a race of demons just like him, as they shared his blue coloring, but Skeletor still appeared to be the only one with a skull head.

10 IT'S NEVER BEEN EXPLAINED HOW HE CAN TALK

Skeletor's voice is iconic. Though some fans might bemoan that actor Allen Oppenheimer turned what might have been a serious and terrifying nemesis for He-Man into a Disney-esque comedy villain, Skeletor might not have had as much staying power in our cultural consciousness for so many years without it. The question remains though: how is Skeletor able to speak? After all, human speech requires a tongue and lips.

The latter Skeletor definitely doesn't have and the former, like his neck, is a big question mark. The inside of Skeletor's mouth is always blacked out so there could well be a tongue in there we just haven't seen. The other answer, of course, is that he uses his magic to give the illusion of a speaking mouth. But, given his telepathic powers, why expend the effort? It might be something we'll never get an answer to.

9 IT'S UNCLEAR IF HE NEEDS TO EAT OR DRINK

Skeletor

Skeletons obviously don't need sustenance to live for... obvious reasons. But, Skeletor isn't a full skeleton, despite his namesake. The rest of his blue-tinted body looks like it's still the same flesh, blood and, presumably, organs from when he still went by the name Keldor. Whether you interpret Skeletor as being undead or not, his body seems to be kept "alive" by dark magic from himself or Hordak.

We can assume that this version of Skeletor probably doesn't need to eat or drink, even if this has never been officially confirmed. But, that doesn't mean he doesn't keep up the facade. In the third episode of the 2002 series, Skeletor sipped on a steaming beverage. Whether it was a piping hot magic potion or a detoxing herbal tea, we'll likely never know.

8 HE WAS UPGRADED BY EATING MAGICAL AMBROSIA

Skeletor

The original nature of He-Man as a line of toys means that varying forms for the franchise's characters have always been an absolute must. Being the primary villain of the property, Skeletor is no exception to this rule. His variant forms include, "Samurai Skeletor," "Terror Claws Skeletor" and "Dragon Blaster Skeletor," which comes with a little pet dragon that can put people to sleep (possibly Skeletor's creepiest weapon.)

His "Battle Sound" form has a food-based backstory. It comes from the episode, "Skywar" of the 2002 series, which saw Skeletor kick-off an inter-tribal war in Eternia just to get his hands on some magical ambrosia to bulk himself up even more. (Think of it has a mystical protein shake.) The deluxe tie-in figure gave Skeletor bigger, spikier armor and the ability to talk.

7 HE HAS A SENSE OF SMELL (BUT NO NOSE)

Skeletor

Just in case you somehow missed it: Skeletor has no nose. This doesn't really matter when you consider that he doesn't really need to eat or drink -- having a sense of taste would be wasted on him. But, we do know for sure that Skeletor can smell things. How do we know this? One word: Stinkor. We discovered this in the 2002 episode, "The Sweet Smell of Victory," which gave the smelly henchman an origin story.

Stinkor -- or, Odiphus -- was mutated by a chemical accident giving him great strength... but also great stench. He approached Skeletor with a request to join his team but the Lord of Destruction kicked him out, covering his face with his hand to prove that even nose-less creatures aren't effected by Stinkor's powers. Clearly, Skeletor's nasal passages are still intact even if the rest of his face isn't.

6 THERE MIGHT BE SOME FLESH ON HIS HEAD

Skeletor

Bones that still have a bit of meat left on them are a lot grosser than ones picked clean. That's why zombies and mummies tend to make us feel a lot more squeamish than skeletons. The question of whether or not Skeletor has a neck relates to how much of his head is just uncovered, and how much of it still has some flesh and skin left on it.

In the '90s New Adventures series, Skeletor was designed to be radically different to how he originally looked in the '80s. The suggestion of a neck was much more solid, his features were rounder and the coloring of his head varied a lot between his standard yellowed hue to more of a sickly green color. Fan speculation is that this color change could be the result of his skin starting to grow back over his skull.

5 SKELETOR'S GHOST

Scare Glow

It's befitting of a skull-headed (possibly) undead wizard to have a ghost among his evil ranks. Scare Glow is a magical spirit at Skeletor's beck and call, but some confusion surrounding his official description led to some interesting speculation about his true identity. Scare Glow's original tagline was the, "evil ghost of Skeletor," and the tie-in comic that came with the toy was named, "The Search for Keldor."

In the story, Skeletor calls Scare Glow to him through "time and space," leading fans to wonder if he was the ghost of Skeletor himself from a future where he'd died. His skeletal body and fondness for purple are very evocative of Skeletor, too. As cool as this is, Mattel's Classics toy line shot this theory down by revealing Scare Glow's living identity to be bounty hunter, Kurak Nul.

4 HIS ARMOR IS LIFE-PRESERVING

Skeletor

The New Adventures of He-Man jettisoned the Masters of the Universe from Earth-bound fantasy romp to futuristic space adventure. He-Man, the defender of the planet Eternia, is called off-world to loan his hero skills to the planet Primus instead. And, who should follow him? His old pal, Skeletor. Both characters underwent significant redesigns -- He-Man got a haircut and finally put some pants on.

Skeletor gained a helmet, hair and some chunky armor. A prequel story in a minicomic tie-in revealed that this armor serves more than a decorative purpose, though. In the story, when Prince Adam finds a way to become He-Man permanently, the powerful energy that radiates from his transformation badly injures his old adversary. Skeletor's new armor is actually just keeping his broken body together.

3 SOMETIMES HE HAS EYEBALLS

Skeletor

Like every other part of his head, the question of how Skeletor sees is a misnomer. Though it appears that he has no eyeballs, some would argue that the red glowing orbs that can sometimes be seen within his skull's eye sockets serve as their replacements, as well as where his energy beams shoot from. Strangely, the few times Skeletor has had visible eyeballs, he just looks even weirder.

His New Adventures redesign very noticeably filled his usually empty sockets with cartoony eyeballs that just looked... wrong. However, in the 1987 movie -- where the medium of live-action made it difficult for the character to not have them -- Frank Langella's SFX make-up was still sufficiently ghoulish, despite not being totally accurate to the toys or original cartoon series.

2 HE'S ALLERGIC TO POLLEN

Skeletor

As we've established through Stinkor's presence, Skeletor does have a sense of smell, despite being, uh, nostril-y challenged. Apparently, what remains of his nasal canals are super sensitive too because he suffers from one of the most common human allergies around: hay fever. In the episode, "Adam's Adventure" of The New Adventures series, Skeletor traps Adam and his buddies to force the Prince to reveal his alter ego.

Quick-thinking Adam uses some instant plant-growth formula he has to hand to be able to transform under some leafy cover. Skeletor uses his magic to mutate the plants into monsters, who He-Man then shoots lasers at, turning them into... flowers? (Hmm...) This has the added bonus of setting off Skeletor's pollen allergy, leaving the villain defeated in the most humiliating way.

1 CYBORG SKELETOR

New Adventures of He-Man Volume 5

What's cooler than a magical, laser-shooting dark wizard with a skull for a head? Just put the word "cyborg" in front of all of that and there you go! When the medieval-esque, fantasy elements of He-Man were stripped out and replaced with more broadly sci-fi ones for The New Adventures series, it was only a matter of time before Skeletor went all Darth Vader. In the miniseries comics that accompanied the show, he indeed becomes cybernetically enhanced.

We may have also gotten another cyborg Skeletor in another medium. A sequel to the 1987 movie was planned, written and went into pre-production with another actor replacing Dolph Lundgren as He-Man, before the first movie even came out. This sequel would have followed the futuristic New Adventures approach, with Skeletor becoming fully mechanized. Unfortunately, the poor box office performance of the first film quickly shut down production.