At one time, adamantium was one of the rarest metals in the Marvel Universe. Now, it seems virtually anybody can lay their hands on the nigh-indestructible metal given the proper motivation and resources. First appearing way back in “Avengers” #66, adamantium was introduced by the legendary creators Roy Thomas, Barry Windsor-Smith and Syd Shores as the alloy used by the evil robot Ultron to construct his metal body.

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Adamantium was made most famous by the X-Man Wolverine, whose trademark claws and skeleton were laced with the stuff. Over the years, many other heroes and villains have made use of adamantium in a variety of inventive ways. From tentacled megalomaniacs to shield-slinging patriots, here are 15 characters other than Wolverine, who prove adamantium is all the rage.

SPOILER ALERT! Spoilers ahead for numerous stories published by Marvel Comics.

15 SABRETOOTH

Adamantium Rage Sabretooth

Originally created by Chris Claremont and John Byrne, Sabretooth first appeared in “Iron Fist” #14 as a recurring villain, who often worked alongside the Constrictor. However, he only gained true notoriety as Wolverine’s arch-nemesis. Like Wolverine, Sabretooth’s mutant abilities include enhanced senses, razor-sharp claws and an accelerated healing factor that allows him to recover from virtually any wound or injury. Basically, he is a faster, stronger, more ferocious version of his favorite sparring partner. For a time, all that was missing was an adamantium-laced skeleton.

Over the years, writers and editors seemed to flip-flop back and forth over whether or not Sabretooth should have adamantium. He gained and lost and regained adamantium enhancements several times over the course of his career, the last infusion of the indestructible metal coming courtesy of the villainous Romulus. He currently runs with the X-Men, helping to fill the void left by Wolverine’s death, while atoning for his past atrocities. If the past is any indication, though, his turn as one of the good guys will likely (hopefully) be a short one.

14 ROMULUS

Adamantium Rage Romulus produces multiple claws from his wrists in Marvel COmics

What’s more dangerous than an animalistic killing machine with three retractable adamantium claws? An animalistic killing machine with four retractable adamantium claws, of course. Romulus’ existence was revealed by Jeph Loeb and Simone Bianchi in 2007’s “Wolverine” #50. Initially he claimed to be the progenitor of an offshoot of homo superior that evolved from canines, but this was revealed to be a hoax by his twin sister Remus. In actual fact, Romulus was merely an extremely long-lived mutant blessed with a healing factor, whose true agenda was the creation of a master race of natural mutants treated with adamantium.

According to Nick Fury, he had been manipulating Wolverine’s bloodline for generations, eventually resulting in the birth of his son Daken. Romulus’ ultimate goal was to become a perfect fusion of Sabretooth and Wolverine, having copied the former’s powers onto his genetic matrix and fusing adamantium to his skeleton and implanting four corresponding claws into his forearms like the latter. Unfortunately for Romulus, all of these upgrades were for naught and he ended up incarcerated on the Raft after one last battle with Wolverine.

13 DEATHLOK (MICHAEL COLLINS)

Adamantium Rage Deathlok

Created by Dwayne McDuffie, Gregory Wright and Jackson Guice, the second incarnation of Deathlok was a man named Michael Collins, a computer programmer for Roxxon Oil, who believed his work on artificial limbs would one day benefit the world. When he discovered Roxxon was using his work to create artificially enhanced killing machines, his brain was transplanted into a powerful cyborg body, where his consciousness was initially subservient to its programming. Collins eventually gained control of the body and became a respected hero, who worked with the Secret Defenders and the Fantastic Four over the course of his relatively brief career.

Collins’ cyborg body was perhaps the most powerful and durable specimen to come out of the Deathlok Project. Built around an adamantium skeleton designed to mimic and enhance natural human motion, Deathlok’s skin and musculature, including his connective tissues, are actually an elastic-steel-adamantium composite that greatly increases his strength, overall durability and resistance to impact. Subsequent incarnations of Deathlok have been far less powerful (if no less formidable), proving they just don’t build ‘em like they used to.

12 HAMMERHEAD

Adamantium Rage Hammerhead

Hammerhead was created by Gerry Conway and John Romita Sr. and first appeared in 1972’s “Amazing Spider-Man” #113. His cartoonish appearance is evocative of classic Dick Tracy villains, who were often conspicuous by their exaggerated, often grotesque appearances. His signature move is to charge at his opponents like a rampaging bull, using his nigh-indestructible melon as a battering ram. A mobster of Russian descent, who lied and killed his way into the Italian mob, Hammerhead’s original steel cranium was given to him by rogue surgeon Jonas Harrow, but was later upgraded to secondary adamantium, a slightly less indestructible version of true adamantium that was retconned into existence when the supposedly unbreakable alloy kept, well… breaking.

While languishing in a prison hospital, Hammerhead took an adamantium bullet to the noggin, courtesy of the Kingpin’s assassin Underworld. This incited Mister Negative to kidnap him from prison and surgically rebuild his skull and upper torso, reinforcing them with more adamantium. Now superhumanly strong as well as virtually unstoppable, Hammerhead’s upgrades came with one painful limitation: an electroshock chip implanted by Mister Negative to keep the unpredictable mobster from going off-script.

11 THE RUSSIAN

Adamantium Rage The Russian

It should come as no surprise that one of the Punisher’s most bizarre and sadistic adversaries was created by legendary collaborators Garth Ennis and the late, great Steve Dillon during their classic “Welcome Back Frank” storyline. Already freakishly strong and nearly impervious to pain during their first encounter, the Russian received significant artificial enhancements, after he asphyxiated to death under an obese man and was beheaded by the Punisher. His remains were snatched up by a clandestine paramilitary organization led by General Kreigkopf and he was resurrected after drastic alterations to his physiology.

Using animal organs, hormone manipulation and an indestructible adamantium skeleton, Kreigkopf transformed the Russian into an unstoppable transgender killing machine, who delighted in his new breasts almost as much as he did in killing his adversaries. Thanks to his new enhancements -- specifically his adamantium-laced bones -- the Russian was able to survive falling off of the Empire State Building and a collision with a subway train. Frank eventually put him down for good by strapping a nuke to his massive carcass and dropping him on the island of Grand Nixon.

10 LORD DARK WIND

Adamantium Rage Lord Darkwind

For years, the complete process of molecularly bonding adamantium to the human skeleton remained a mystery. The experimental procedure used by the Weapon X program on both Wolverine and Sabretooth relied upon the incomplete research of a Japanese scientist and criminal mastermind named Lord Dark Wind and the subjects’ own accelerated healing factors to ensure success. Lord Dark Wind first appeared in 1983’s “Daredevil” #196, created by Denny O’Neil, Larry Hama and Klaus Janson as the man who repaired Bullseye’s broken spine.

Using the correct, complete procedure, which included the use of a special herb to prevent the body from degenerating during the bonding process, Lord Dark Wind was able to reinforce Bullseye’s spine and several other bones with adamantium. Although he would ultimately perish at the hands of his daughter Yuriko, during his final showdown with Daredevil, she would later embrace Lord Dark Wind’s legacy and submit herself to the bonding process, becoming one of Wolverine’s deadliest and most implacable foes.

9 DONALD PIERCE

Adamantium Rage Donald Pierce

Another villain created by Chris Claremont and John Byrne, Donald Pierce first appeared as a member of the Hellfire Club’s Inner Circle in 1980’s “Uncanny X-Men” #132. Revealed as a cyborg after Wolverine cuts off his arm, Pierce reveals he hates all mutants and only joined the Hellfire Club in order to kill the Inner Circle, all of whom are of mutant origin. Over the years, the resourceful and resilient Pierce has used his knowledge of cybernetic engineering to switch out several body parts with artificial replacements.

Pierce gave himself a massive upgrade after he was literally cut loose from an escape helicopter by Sebastian Shaw after a failed bid to rejoin the Hellfire Club. Using a hidden cache of adamantium belonging to Cable, he reinforced his body just in time to take on Wolverine and Jubilee. The battle didn’t last long before a mysterious being named Khyber waltzed in out of nowhere, claiming Pierce stole his tech and proceeding to beat the holy hell out of the cyborg with one of his own dismembered arms. He then disappeared, never to be seen again.

8 DAKEN

Adamantium Rage Daken

Daken was created by Daniel Way and Steve Dillon and first appeared in “Wolverine: Origins” #6. Unlike most other entries on our list, Wolverine’s estranged son never relied on adamantium to enhance his natural mutant abilities. Although blessed with many of the same powers as his old man, including retractable claws, superhumanly acute senses and a robust healing factor, Daken’s body remains an adamantium-free zone, except for one minor adjustment. After coming into possession of a piece of his father’s broken Muramasa blade, Daken has the Tinkerer coat his inner claws in the fragment.

Due to the Muramasa’s mystical ability to retard mutant healing factors, the Tinkerer also installed adamantium sheaths in Daken’s wrists to prevent accidental contamination. As understated as this use of adamantium is, it stands apart from typical applications for its practicality and functionality. Remaining true to himself and his abilities, Daken utilizes the adamantium as a tool rather than fall into the trap of using it as a crutch; a pitfall many other users, such as his former trainer Cyber, failed to avoid.

7 LADY DEATHSTRIKE

Adamantium Rage Lady Deathstrike

Lady Deathstrike was once Yuriko Oyama, the long-suffering daughter of Lord Dark Wind, the criminal genius responsible for creating the molecular bonding process that fuses adamantium to human bone. Although she killed her father for his various abuses over the years, the suicide of her lover spurs Yuriko to reconsider her father’s scientific legacy. She embarks on a quest to recover his lost work by tracking down Wolverine’s adamantium skeleton, which was enhanced using an incomplete set of notes stolen from her father’s research.

Although she was ultimately unsuccessful in gleaning the secrets hidden by Wolverine’s skeleton, Lady Deathstrike was relentless in her pursuit of adamantium enhancements. Her search led her to Spiral’s Body Shop, where the indestructible metal was magically fused to her skeletal structure. Her fingers were replaced by 12-inch retractable adamantium claws capable of doubling in length. Later, through her association with Donald Pierce’s Reavers her cyborg body was modified further, providing her with extensive self-repair capabilities of both her organic and artificial parts. Long considered one of Wolverine’s most formidable rogues, Lady Deathstrike was left feeling empty by his sudden death, robbed of the opportunity to kill him herself.

6 CYBER

Adamantium Rage Cyber

Created by Peter David and Sam Kieth, the man known as Cyber first appeared in “Marvel Comics Presents” #85, as an assassin built specifically to kill Wolverine. He first encountered Wolverine during World War I and gave the future X-Man his first real whooping, gouging out his eye in a one-sided brawl. Later, he was recruited by Romulus to train Logan’s son Daken, whom he considered the best student he ever tutored. A mutant born with superhuman strength and a psionic tracking ability that lets him trace brain wave patterns around the world, Cyber also benefitted from a number of later artificial enhancements.

Thanks to Romulus, Cyber’s entire epidermis, excluding his face, was covered in a second adamantium skin using an experimental arc welding procedure. Adamantium claws were surgically implanted in his fingers, their tips laced with various poisons and hallucinogenic drugs. Although he was essentially designed to kill Wolverine, Cyber would ultimately succumb to heart attack, after a carbonadium pacemaker failed to stabilize a bum ticker. His corpse was last seen in the possession of Ogun, who claimed to have killed him so he could harvest the adamantium from his flesh.

5 DOCTOR OCTOPUS

Adamantium Rage Doc Ock

Widely considered to be one of Spider-Man’s most fearsome foes, Otto Octavius was created by Stan Lee and Steve Ditko and first appeared in “Amazing Spider-Man” #3, way back in 1963. A brilliant physicist and inventor, Octavius created a set of four titanium tentacles attached to a harness that enabled him to perform precision experiments with nuclear radiation. When an explosion fused the harness to his body, he was transformed into a maniacal super-criminal, who used his telepathically-controlled arms to terrorize Spider-Man as Doctor Octopus.

Over the course of his long history, Doc Ock used three different tentacle harnesses, the second of which was composed of adamantium. The harness’ adamantium arms greatly increased Doc Ock’s effectiveness and overall power level, allowing him to go toe-to-tentacle with the Hulk and tear open the so-called invincible Iron Man like a tin of sardines. Alas, the harness was somewhat less than indestructible itself and was destroyed during the 1993 limited series, “The Lethal Foes of Spider-Man.” It’s probably just as well. Old Otto eventually got the upper hand on his arch-nemesis, at least for a time, when he took over Peter Parker’s body as the Superior Spider-Man.

4 BULLSEYE

Adamantium Rage Bullseye

Of all the adamantium-laced killers on our list, only Bullseye has the distinction of enduring Lord Dark Wind’s molecular bonding process in its entirety. Created by Marv Wolfman and John Romita Sr., Bullseye first appeared in “Daredevil” #131 but remained a B-list Daredevil villain until Frank Miller transformed him into a sadistic assassin, obsessed with making a name for himself, by killing his arch-nemesis. Although ultimately unsuccessful in that regard, Bullseye did manage to hurt ol’ Hornhead like few others have, by killing his lover Elektra. Enraged by Elektra’s murder, Daredevil ends their climactic battle by dropping Bullseye several stories onto the electrical lines below, shattering his body.

Seizing an opportunity to build his own superhuman assassin, Lord Dark Wind frees Bullseye and repairs his body by grafting adamantium onto his spine; using a secret herbal treatment to ensure he survived the process. The procedure reinvigorated Bullseye, lending an element of resiliency to his already formidable skillset -- even if it didn’t prevent Daredevil from dispatching him during Shadowland. Resurrected some time ago, Bullseye currently stars in a brand new miniseries by Ed Brisson and Guillermo Sanna, seeking to re-establish his reputation as the world’s most lethal assassin.

3 ULTRON

Adamantium Rage Ultron

As we already noted in our introduction, without Ultron, there very likely wouldn’t be a substance called adamantium. First built by Hank Pym in “Avengers” #54, Ultron was created by comic book legends Roy Thomas and John Buscema. However, the maniacal artificial intelligence wouldn’t become a true force to be reckoned with, until eight issues later, when adamantium was first introduced to the Marvel Universe. When the Avengers are invited by S.H.I.E.L.D. to try and destroy a sample of Dr. Myron MacLain’s new alloy, they are seemingly betrayed by the Vision, who, under Ultron’s control, steals the priceless metal.

With the Avengers occupied trying to free a trapped Iron Man, the Vision builds Ultron’s first adamantium body, setting a precedent for all future versions of the killer robot, making it virtually indestructible. To this day, despite being dropped into the heart of the sun by the Avengers Unity Division, Ultron remains one of the Marvel Universe’s most dangerous villains, thanks in large part to his adamantium shell, which makes him virtually impossible to destroy.

2 CAPTAIN AMERICA

Adamantium Rage Captain America

Although the primary material of Captain America’s iconic round shield is vibranium, it is actually composed of two other materials: steel and an unknown catalyst accidentally introduced into Dr. Myron MacLain’s original formula while he took a catnap. This happy accident resulted in the only known sample of what is now known as “proto-adamantium.” MacLain was never able to replicate the experiment but would later create “true” or “primary” adamantium, an easily reproducible alloy that was eventually grafted onto Wolverine’s skeleton.

If calling Cap’s shield adamantium rather than vibranium offends your comics sensibilities, then let’s consider the shield a disillusioned Steve Rogers carried as the Captain. When the U.S. government attempted to appropriate the Captain America identity for its own ends, Rogers resigned in protest and created a new crimefighting persona called the Captain. As the Captain, Rogers carried a new shield of pure adamantium, constructed by Tony Stark, until the two had a falling out during “Armor Wars” and he returned it.

1 WOLVERINE (LAURA KINNEY)

Adamantium Rage Wolverine

Okay, so maybe we’re hedging our bets here, by making the current Wolverine our top entry. However, Laura Kinney is a distinct, vibrant character in own right, who more than lives up to the old man’s legacy. Created by Craig Kyle and Chris Yost, Laura first appeared as the feral X-23 in “NYX” #3. There are some noticeable differences between the two Wolverines. Unlike her father Logan, Laura only possesses two claws on each hand but boasts a single claw on each foot, allowing her a more dynamic array of attacks.

Furthermore, only Laura’s claws are coated in adamantium. The rest of her skeleton, while stronger and more durable than a normal human’s, isn’t unbreakable. This means she could conceivably break her own wrists and hands if she tries to use her claws on a substance she isn’t strong enough to pierce. At first blush, these differences may appear to be weaknesses and perhaps they are to some degree, but they could also be considered obstacles to be overcome, challenges to be surmounted that help make Laura even more endearing and intriguing a character than her virtually-unkillable dad.

Think you’re metal? Let us know who else uses adamantium in the comments!