Kryptonite -- deadly, radioactive shards of Superman's home planet -- has existed for almost as long as the Man of Steel himself. As such, dozens of strange variations on its original green form have been cropping up for decades throughout comic book continuity, but also in all of Superman's extended media, too. The idea for a power-draining substance was masterminded in 1940 by co-creator Jerry Siegal as "The K-Metal from Krypton," but the story was rejected and fell into obscurity. The first official use of the word "Kryptonite" didn't happen until three years later, and it was in the radio serial, The Adventures of Superman, not the comics. Kryptonite finally made its comic book debut in 1949 in Superman #16, but it was red rather than green. In fact, naturally green Kryptonite -- its most well-known form -- didn't officially pop up until Action Comics #151.

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In Pre-Crisis continuity, a whole rainbow of real, synthetic and fake versions of Kryptonite seemed to be forever materializing across the different Earths. The Silver Age saw Superman assaulted by an endless slew of different Red K chunks that all produced bizarre mutations, new abilities and cosmetic changes in him. Post-Crisis, green was established as the only natural form, but that hasn’t put an end to yet more (artificial) forms causing problems for Superman and the Super-family. Whatever era or medium it appears in, certain forms of Kryptonite have created some pretty weird effects. Here are the 15 strangest!

16 BLUE

Blue kryptonite

Blue K was originally only supposed to affect Bizarro, Superman’s intelligence-deprived clone. This Kryptonite variation mirrored the idea of Bizarro as a backwards Superman, by acting essentially as the equivalent of Green K for Bizarros, with much the same power-draining effect. It first appeared in Superman #140 in 1960, as part of a three-part story called “The Son Of Bizarro,” which introduced us to the creatively named, Bizarro Jr. (Bizarro Superman and Bizarro Lois’ son). To thwart his Bizarro foes, Superman manufactures Blue K (or “Bizarro Kryptonite”) using the device that Lex Luthor made Bizarro with -- the Duplicator Ray -- on some Green K.

Blue K also appeared a few times in the TV show Smallville, which followed the formative years of Clark Kent before he donned the cape and tights. First appearing in Season Seven in the episode appropriately titled, “Blue,” the substance's odd effects were drastically altered in the show to enhance rather than drain the powers of Bizarros. It also de-powered Kryptonians, and invigorated all other organic life. In the 2010 DC animated movie, Justice League: Crisis on Two Earths, Ultraman was also proven be weakened by it.

15 YELLOW

Yellow Kryponight

There seem to be almost as many fake versions of Kryptonite lying around as there are bonafide, real ones. Yellow K is one such phoney form. It appeared (for the first and seemingly last time) in Action Comics #277 in 1961 during, “The Conquest of Superman.” The story is an all-too familiar one: while Superman is adventuring off-world, disaster strikes on Earth leaving those in charge apparently no choice but to free an incarcerated Lex Luthor to help. However, true to dastardly form, Luthor immediately turns on the authorities when Earth is out of peril and escapes jail.

His next move is (predictably) to bump up his finances. After looting some gold from Fort Knox, Superman suddenly shows up to stop him. Luckily, Luthor came prepared, scaring him off with some Kryptonite. Back at his Lair, the supervillain gloats over the yellow rock actually being a fake, only to discover that the Superman he thought he’d tricked was also a fake -- one of Superman’s robotic sentries.

14 MAGNO

Magno Kryptonite

This strange and relatively obscure form is another artificial variation, with seemingly no basis in Kryptonian materials. It first popped up in the Superman spin-off comic series, Superman’s Pal, Jimmy Olsen #92 in 1966 in “The Man From S.C.A.R.,” which sees the Jimmy Olsen confront his body-double and go all James Bond to find out where the clone came from. The man behind it all turns out to be a criminal mastermind called “Mr. Nero,” who then turns out to really be an evil alien with a penchant for arson.

Nero is a dab-hand at manipulation and inventing, two skills he combines to create a deadly implant that forces Jimmy to obey him, and Magno-Kryptonite, to fend off interference from Superman. As the name suggests, Magno-K is magnetically attracted to anything of Kryptonian origin. So great is its pull, Jimmy notes that not neither Superman nor Bizarro can resist it.

13 BLACK

Black Kryptonite

Smallville delved deeply into Superman mythology, including introducing unfamiliar fans to a wide variety of Kryptonite forms beyond just the famous Green kind. But it also added to the mythology too. Black K was introduced in Season Four in the episode “Crusade." It is derived from the original Green form through superheating. It has the strange ability to split the personalities of Kryptonians, and sometimes humans. In the young Superman’s case, this forged a split in his psyche between his Clark Kent and Kal-El identities.

During the Season Eight episode, “Doomsday,” Chloe similarly used it to physically free David Bloome from his Doomsday identity. The substance did end up jumping from screen to page, though. Debuting in Supergirl #2, where Black K caused the same split within Supergirl’s body, creating a “good” and black-costumed “bad” version of her.

12 BLOOD

Blood kryptonite

This vampiric-sounding variation comes with the dark origin story you’d expect. It’s another forgery derived from the original Green form, and first appeared in 52 #13, during the timeline that fills in the “lost year” between Infinite Crisis and One Year Later. This rock appears to be green, despite its name, and is passed around by the “Cult of Conner” -- a group sworn to revive the then dead Superboy -- during one of their ceremonies.

Amongst the cult members, a disguised Hal Jordon remarks that “Blood Kryptonite” is nothing more than a “painted rock.” Nonetheless, during the ritual, modelled after a Kryptonian resurrection ceremony, the rock does have a strange effect, directing the life force of those present into the body intended to be brought back to life.

11 SILVER

Silver Kryptonite

The silver form of Kryptonite is one of the more commonly known types. It’s also one that’s produced a wild variety of effects over the years through its use in different Superman-related media. Its first appearance was actually a practical joke played on Superman by (who else?) Jimmy Olsen in #70 of Superman’s Pal, Jimmy Olsen in 1963 during the story, “The Secret of Silver Kryptonite.” Spoiler alert: the secret is that it’s not really Kryptonite. The prank was pulled to mark Superman’s Silver Anniversary.

But the hoax form was resurrected by Smallville in Season Five as a “newly discovered” form of meteor rock, delivered to Lana Lang by Professor Milton Fine to infect Clark, inducing extreme paranoia in him. Revealed to be a Kryptonian experiment, the silver rock could also take liquid form, of which supervillain Braniac (disguised as Milton Fine) was composed. In Superman/Batman #46, it returned to comics, and seemed to have the effect on Kryptonians that a certain drug does on humans -- hallucinations, food cravings and a more, uh, “mellowed” vibe.

10 SLOW

Slow Kryptonite

This version appeared in The Brave and The Bold #117 in 1981 and was concocted by super villain Metallo. Metallo is a Terminator-esque cyborg powered by Kryptonite who will often stop at nothing to achieve his evil aims, so it’s unsurprising that he’d try to manipulate his very life source to do harm to others. In the story, he manages to modify Green K to affect humans rather than Kryptonians, which honestly seems a little counter-intuitive to his usual, single-minded purpose, which normally involves taking down his arch nemesis, Superman. The effect on humans is similar to the effect it usually has on Kryptonians, one which the cyborg achieved by manipulating the rock to emit “slower” rays than it normally does, to better suit human physiology -- hence the name choice.

9 PURPLE-SPOTTED

Purple spotted Kryptonite

This funky-coloured variation of the radioactive rock appeared exclusively in the animated show, Krypto the Superdog. The Superman spin-off show aired between 2005-2006, focussing on the exploits of Superman’s super-powered canine sidekick and a whole host of other animal-themed heroes, including “Streaky the Supercat,” “Ace the Bathound” and “The Dog Star Patrol”. During the series, Krypto encounters many different forms of Kryptonite in the way his master continually does.

His arch enemy, a cyborg feline named “Mechanikat,” always seems to have some spare Green K handy, while chunks of Red K have caused him to lose his memory. The Purple-Spotted variety, featured in one story, made up by Streaky, produced one of the strangest fictional effects -- forcing Krypto to chase his own detached tail.

8 KRIMSON/MAGICAL

Krimson Kryptonite

Not to be confused with Red Kryptonite, this magical version is one of many fakes that have been crafted by beings with supernatural powers. One of the weirdest instances of this was during a storyline in Superman’s Pal, Jimmy Olsen #42 in 1960 in which Jimmy attempted to launch a Hollywood career and was transformed into a Genie. (You decide which is more farfetched.) His maniacal master “Abdul” then ordered Genie Jimmy to trans-mutate into a magical version of Green K to take down Superman.

“Krimson” or “Magic” Kryptonite is one of the few fake forms derived from Red K rather than the more common Green variety. It featured in the alliteratively-named storyline, “Krisis of the Krimson Kryptonite” in Superman #49 in 1990, and weaponized by Lex Luthor against Superman. However, it turned out to not only be completely fake, but it actually the reality-warping trickster, Mr. Mxyzptlk, in disguise.

7 ORANGE

Orange Kryptonite

This is another version that’s so far exclusive to the world of Krypto The Superdog. Not to be mistaken for Gold or Yellow K, it was featured in #4 of Cartoon Network’s comic book adaptation of the animated series in 2007, in the storyline, “The Purr-fect Crime.” The cover appropriately carried the slogan, “Beware of the Orange Krypto Night!” In the story, “Snooky Wookums” -- the intellectual sidekick to Krypto’s arch-villain, Mechanikat and “Isis,” female companion to Catwoman/ love interest for Streaky -- stumble across the rare, tangerine-tinted rock, which grants them superpowers.

It’s left up to Krypto, with help from Ace, Streaky and The Dog Star Patrol (a canine version of the Legion of Superheroes) to de-power them. As this variety hasn’t yet featured anywhere outside of the Krypto-verse, we have no idea if it would have the same effect on non-animals.

6 WHITE

White Kryptonite

White Kryptonite can kill instantly within a range 25 yards, making it one of -- if not, the -- most deadly forms. Oh, but it only works if you’re a plant or form of microscopic life. It cropped up in quite a number of Action Comics storylines during the Silver Age, one of the earliest being Action Comics #278 in 1961, during the story, “The Super-Powers of Perry White!” As the name suggests, Daily Planet Editor in Chief is imbued with superpowers after becoming the unwitting host to a plant-based alien parasite, “Xasnu.”

White even comes close to getting the best of Supes, until Supergirl comes flying to his rescue to destroy Xasnu with some White K. White K was later used to cure Superman of Virus X (Kryptonian “Super Leprosy,” sounds nasty) and was revealed in Action Comics #362-366 in 1968 to in fact be plant-based.

5 JEWEL/GEMSTONE

Jewel kryptonite

Jewel Kryptonite made its sparkling debut in Action Comics #310 in 1964 - drawn by the renowned Silver Age artist, Curt Swan. On the cover, Superman poses in front of Jimmy Olsen - camera at the ready - with five differently coloured fake Kryptonite rocks, proclaiming them to be the “only five types in existence.” Little does Supes know that a sixth type (Jewel) has been hidden in Jimmy’s camera… This multi-tinted version came from Krypton’s Jewel Mountain range and grants those in the Phantom Zone psychic powers.

Its powers in Smallville, however, are far different and far weirder. Renamed “Gemstone Kryptonite,” it appeared in Season Nine in the episode, “Persuasion.” Clark eats some Valentine’s Day chocolates laced with the rock in powder form, and suddenly, his every word is obeyed by those around him. This results in the shocking sight of the career-driven Lois Lane becoming a subservient, domestic goddess.

4 X

X Kryptonite

This one should not be confused with Kryptonite-X/Kryptisium. Many of the strangest forms of the Kryptonian space rock are created by experimentation - either magical or scientific - mostly for anti-Superman reasons. Metallo has tried his robotic hand at it, Mr. Mxyzptlk did it to give Lex Luthor a fright, and Jimmy Olsen seems to curiously come into contact with more fake K than most of Superman’s villains put together.

X-Kryptonite is another version that came about through tinkering with the original Green stuff, and Supergirl is to blame for its existence. Her intentions were good, though. While hoping to find a cure to Green K’s harmful effects on Kryptonians in a 1960 storylines in Action Comics #261, she instead creates a new form that ends up giving her cat, “Streaky,” superpowers. Naturally, he quickly gets his own cape and superhero title.

3 MENTALLIUM

While not strictly Kryptonite, it might as well be. These space rocks appear in Grant Morrison’s Flex Mentallo mini-series in 1996, using the titular character he created as a Silver Age hero, pulled from his Doom Patrol series. The four stories in the Flex Mentallo solo series were intended as meta-commentary on the Golden, Silver, Bronze and Modern Ages of comics, ripping comic books apart and then attempting to piece them back together.

Suitably, Mentallium is a clear parody of the Kryptonian space rocks, with each ludicrous effect spoofing the weirder forms of Kryptonite. Each of the five rocks hover where the head of Flex’s villain, “Mentallium Man”’s head should be and effect Flex in different ways. Black kills him; Silver takes away his sense of humor; Ultraviolet makes him think he is someone else; Pink compels him to discuss issues around gender and sexuality; and Lamb & Turkey… well, no one actually knows what they do, but it's probably super weird.

2 PINK

Pink Kryptonite

Ever wondered if Superman would be any different if his sexuality changed? Well, Pink Kryptonite allows you to wonder no more! Sort of. And very briefly. In 2003’s Supergirl #79, pre-Crisis Supergirl, Linda Danvers, ends up taking the place of Kara Zor-El in the normal DC universe. The Pink variant shows up in just one panel, but its sensational effect on Supes left quite a lasting imprint on readers. In the panel in question, a confused Lois tells Linda that Clark has been acting “awfully” strange after being exposed to the rare form of Kryptonite, while in the foreground, Clark compliments a befuddled Jimmy Olsen on his “smashing” tie and “fabulous” window arrangement. The stereotyped implication here of course being that Clark’s interest in women has suddenly disappeared. Writer Peter David explained that this was meant as a tongue-in-cheek tribute to the “innocent times” of the Silver Age.

1 RED

Red Kryptonite

After Green, Red is the most well-known form of Kryptonite, and it’s without a doubt also the weirdest in terms of the variety of effects it’s had on Supes over the years. There were some strange instances in the TV adaptations -- extreme laziness in Lois & Clark: The New Adventures of Superman and an extreme case of “bad boy-itus” in Smallville. But, the Silver Age comics are (of course) where you’ll find the craziest examples.

Red K has caused Superman to: grow a beard (Superman #39, 1960); become trapped in the body of a toddler (Action Comics #284, 1962); command an army of giant ants (Action Comics #296, 1963); grow to King Kong size (Superman #226, 1973); change the colour of face like a mood ring (Action Comics #317, 1964); breathe fire; grant wishes (Action Comics #283, 1961); develop super-stretching powers (Action Comics #299, 1963); and lose his powers… but only on the left side of his body (Action Comics #290, 1962).

Superman #25, the conclusion of the “Black Dawn” storyline, goes on sale July 21.

What is your favorite form of kryptonite? Let us know in the comments!