Real Name: Unit Four

Identity/Class: Terrestrial android (Life Model Decoy)

Occupation: Iron Maniac's armor; former Red Skull agent

Group Membership: None

Affiliations: Captain America (Steve Rogers), Iron Maniac (Tony Stark) of Earth-5012, S.H.I.E.L.D. (especially Nick Fury, Mark Nolan), Senator Richard Winslow;
   formerly Red Skull (Johann Shmidt)

Enemies: Hydra, Red Skull (Johann Shmidt), Serpent Society (Anaconda/Blanche Sitznski, Asp/Cleo Nefertiti, Black Mamba/Tanya Sealy, Black Racer/Ariana Saddiqi, Bushmaster/Quincy McIver, Coachwhip/Beatrix Keener, Fer-de-Lance/Teresa Vasquez, King Cobra/Klaus Voorhees, Puff Adder/Gordon Fraley, Rattler/Gustav Krueger, Rock Python/M'Gula, Sidewinder/Gregory Bryan);
   formerly Iron Maniac (Tony Stark) of Earth-5012

Known Relatives: None

Aliases: Rachel Leighton

Base of Operations: Mobile with Iron Maniac;
   formerly Rachel Leighton's apartment in New York City, New York

First Appearance: Captain America IV#29 (September, 2004)

Powers/Abilities: Unit Four was an advanced Life Model Decoy with vast shapeshifting capabilities and superhuman strength, though she was limited by her own programming to merely duplicate the enhanced physical abilities of the real Diamondback. She could subconsciously tap into her actual superhuman strength, speed, agility, resistance to physical harm and self-repair program if needed.

   She possessed the full memories of Diamondback with additional memories added to turn her against Captain America. (see comments)

   Like other LMDs of her line she became unstable upon learning her true nature.

   The Diamondback personality could be deleted by deactivating the LMD. After a complete reset the LMD could be returned to its raw form after which a new mind scan could be uploaded or a neural link could be established to use the shapeshifting capabilities of the LMD in every possible way. The LMD could even be turned into an armor with boot jets and the ability to discharge electricity. Even as armor the shapeshifting capabilities of the LMD remained a powerful and deadly tool turning parts of it into a variety of tendrils or spikes with a mere thought.

Height: Variable; (as Diamondback) 5'11"
Weight: Variable; (as Diamondback) 153 lbs. (by approximation)
Eyes: Variable; (as Diamondback) Green
Hair: Variable; (as Diamondback) Brown

(Captain America IV#32 (fb) - BTS) - S.H.I.E.L.D. developed a series of improved and advanced Life Model Decoys, but they were not approved for use yet because they worked too well and actually believed themselves to be whoever they were supposed to replace and became mentally unstable and dangerous when they were told of their true nature. A brain scan of Diamondback (Rachel Leighton) was downloaded into Unit Four, one of these new Life Model Decoys, in such a way that it became a perfect reproduction of Diamondback's mind.

(Marvel Team-Up III#21 (fb) - BTS) - These new LMDs possessed shapeshifting capabilities...

(Captain America IV#32 (fb) - BTS) - ...and vast self-repair protocols.

(Captain America IV#32 (fb) - BTS/Marvel Team-Up III#6 (fb) - BTS) - Rogue S.H.I.E.L.D. agent Mark Nolan stole Unit Four and activated it prematurely after inputting commands that contradicted the original Diamondback's behavior. The new commands melded with her personality without her even realizing the conflicting thoughts. Nolan had the LMD programmed to only respond to his own voice command, planning to double-cross the Red Skull, whom he sold the brainwashed LMD to.

(Captain America IV#29 (fb) - BTS) - The Diamondback LMD secretly started working for the Red Skull as it was programmed to do.

(Captain America IV#32 (fb) - BTS) - The LMD was sent to Captain America's doorstep by Nolan.

(Captain America IV#29 (fb) - BTS) - The Diamondback LMD waited for almost an hour on Captain America's doorstep.

(Captain America IV#29) - Unaware she was an LMD Steve Rogers greeted the LMD and invited her to come up to his apartment and watch the digitally remastered Yankee Doodle Dandy he had just rented. The LMD wondered why he was still renting this movie, but was up for it. Asked by Steve what she was doing in his neighborhood she revealed she just wanted to take the initiative and look him up because they were once an item. After arriving in his apartment Steve received a call from Nick Fury (actually Nolan posing as Fury via holographic device). "Fury" asked Steve to accompany him to his Sub-Carrier and while Steve put on his costume asked Diamondback if she and Steve were together again, which Diamondback jokingly denied especially if Steve kept forcing her to watch those old movies over and over again. Cap asked Diamondback if she wanted to tag along and she gladly did. Utilizing a jetpack provided by "Fury" Cap carried Diamondback to the Sub-Carrier where "Fury" asked Cap to save Senator Richard Winslow, who had been kidnapped by Hydra (actually Winslow paid Nolan for the whole scenario to get some favorable footage of Cap saving him...unfortunately Hydra apparently wasn't in on it and Winslow got actually scared).

   Diamondback joined Cap on the mission. At the drop point she jumped out the Sub-Carrier with a jetpack alongside Cap, who remained unaware that "Fury" was actually rogue S.H.I.E.L.D. agent Mark Nolan and that the Red Skull was on board the Sub-Carrier as well. They descended upon Hydra's Florida Keys base under heavy fire and fought their way through numerous Hydra agents. They eventually found Winslow and escaped with him after defeating more Hydra agents before returning to the Sub-Carrier.

(Captain America IV#29 - BTS) - Diamondback and Cap rested in their quarters in the Sub-Carrier while it headed back to New York.

(Captain America IV#29) - The next morning "Fury" thanked Cap and Diamondback, who returned their jetpacks to "Fury" as soon as they landed in New York City. Cap apologized to Diamondback because "Fury" dropped her off so far away from her own apartment, but she didn't plan to return home anyway. Before she could say anything else Cap was called away by an Avengers priority alert, forcing Diamondback to return home where the Red Skull was already waiting for her. She assured Red Skull that everything was going according to his plan because she and Cap would see each other again.

(Captain America IV#30) - Steve attended a New York Mets baseball game with Rachel. The game was interrupted when the Mets' mascot Mr. Met took off its mask to reveal a terrorist, who threatened to blow up the stadium if not everyone in the stands handed over their jewelry, watches and cash to his men. Steve put on his costume and asked Rachel to take out the henchmen in the stands while he took out their leader. Cap defeated Batroc, the actual leader, after realizing he was holding an ink pen and not a detonator. Batroc's henchmen then surrendered. Afterward outside the stadium Rachel asked Cap how he knew it was only an ink pen and he told her that it was too light and had a hole in the bottom. Young fans surrounded Cap to get his autograph, forcing Rachel to wait. They arrived back at Cap's apartment in the evening and Rachel stayed overnight.

   Rachel slept in, then left to run some errands and promised to see Cap in the evening to watch Yankee Doodle Dandy with him again.

   Rachel met with Red Skull and told him how obsessed Cap was with Yankee Doodle Dandy. Red Skull asked her to bring a bottle of wine to her date with Cap and then gave her poison to put into Cap's glass. Rachel smiled while Red Skull already triumphantly raised his fist because in a few hours Cap would be dead.

   Rachel arrived with a bottle of wine at Steve's apartment. He got two glasses from his cupboard, poured some wine into the glasses and while he put the DVD into the DVD player Rachel poured Red Skull's poison into Steve's glass. Steve was seconds away to drink the poisonous wine when the Serpent Society's Bushmaster, Puff Adder and Asp crashed through the wall to attack Rachael and Steve. Asp hit both with a venom-bolt and was surprised when Rachel remained conscious and even hit her in the face. Puff Adder knocked out Rachel from behind, hurting his fist in the process.

(Captain America IV#30 - BTS) - While they were unconscious the Serpent Society put Steve and Rachel into their costumes.

(Captain America IV#30) - Surrounded by King Cobra and his Serpent Society Cap and Diamondback awakened chained to a column in the Serpent Society's base. King Cobra explained that the Serpent Society still had a score to settle with Diamondback and wondered how stupid she was for showing herself in front of a camera in New York City during her little adventure in the Mets' stadium.

(Captain America IV#31) - King Cobra threatened the chained up Diamondback with torture and abuse while he told Cap that he would be sold off to the highest bidder in an auction. Diamondback was annoyed when Cap could only think about late fees he was going to pay for the rented Yankee Doodle Doo movie.

   16 hours later Cap and Diamondback were still chained to the column at the Serpent Society's base. King Cobra had Cap taken down by Anaconda and Puff Adder to bring him to the auction and then promised Diamondback he would get his full attention soon. Cap managed to kick his shield from King Cobra's arm and ricochet it off the wall to break his chains. After knocking out Anaconda and Puff Adder, Cap failed to stop King Cobra from calling in reinforcements. Cap freed Diamondback so she could join him in battle against the rest of the Serpent Society. While Cap knocked out Asp, Black Mamba, Bushmaster, Coachwhip and Rattler, Diamondback easily knocked out Black Racer, Fer-De-Lance, Puff Adder, Rock Python and Sidewinder, impressing Cap, which meant a lot to her. Cap called Nick Fury to send someone to pick up the defeated members of the Serpent Society.

   Heading back home Diamondback apologized to Cap for the Serpent Society's attack, but Cap was glad that he could help her and they kissed. Diamondback offered Cap to stay over night at her place because his place had been demolished by the Serpent Society's attack. Cap was happy to join her after making some calls to set up repairs for his place.

   Diamondback arrived back home after buying groceries and was startled by the Red Skull, who asked her to assassinate Cap that night the old-fashioned way after she failed to do so the night before due to the Serpent Society's interruption. Diamondback revealed that she had couldn't kill Cap anymore because she had fallen in love with him and after he saved her at the Serpent Society's HQ. Angered by the revelation the Red Skull deemed her useless and snapped her neck. Moments after her seeming demise Cap knocked on Diamondback's door.

(Captain America IV#32) - The Red Skull dropped the corpse of Diamondback and attacked Captain America, who discovered her corpse moments later. When the whole building collapsed due to the damage done to it by the fight between Cap and the Red Skull, Diamondback rose from the debris to the surprise of Cap and the Red Skull. Her LMD body repaired itself in front of them and Diamondback attacked the Red Skull. Diamondback helped Cap to his feet and neither of them understood what was going on with her. Diamondback explained how she was able to rebuild herself after her neck was broken and she was nearly crushed when the building collapsed. Diamondback attacked the surprised Red Skull with full force, nearly choking him to death. Fury arrived and used a command on the Diamondback LMD aka. Unit Four to stop her from moving.

   While Fury explained to Cap that the Diamondback he was working with was actually an LMD brainwashed to work with the Red Skull, the LMD itself remained paralyzed by Fury's command. Unable to believe what was going on with her the LMD was put into an LMD containment pod by S.H.I.E.L.D. agents while she was pleading with Cap to not let them take her away.

(Marvel Team-Up III#6 (fb) - BTS) - Fury didn't know what to do with the malfunctioning Diamondback LMD. He didn't want to just deactivate it because it actually believed itself to be the real Diamondback, but he also couldn't allow it to be on the loose. Fury eventually decided to shut the Diamondback LMD down and keep it in a stasis pod on a Helicarrier until S.H.I.E.L.D. found a way to fix it.

(Marvel Team-Up III#6) - When Cap saw the Diamondback LMD kept in a stasis pod on the Helicarrier he was disappointed that this was the best Fury could do for her. Fury explained the situation and promised he would let her out as soon as his men found a way to fix her programming.

(Fantastic Four: Foes#4) - The Diamondback LMD remained in a stasis pod on the Helicarrier.

(Marvel Team-Up III#13 (fb) - BTS) - The Diamondback LMD was moved to a containment box on the Helicarrier.

(Marvel Team-Up III#13) - Nick Fury, Wolverine and Spider-Man walked by a containment box the shut off Diamondback LMD was kept in on the Helicarrier.

(Marvel Team-Up III#21 (fb) - BTS) - The Diamondback LMD was returned to a stasis pod in the cryogenics room on the Helicarrier.

(Marvel Team-Up III#21) - The Diamondback LMD was kept in a stasis pod in the same room as the mad Tony Stark of Earth-5012.

(Marvel Team-Up III#22) - Earth-5012's Tony Stark escaped from his pod and released the Diamondback LMD, who recognized him as Tony Stark. The LMD still believed itself to be Diamondback, that S.H.I.E.L.D., Hydra or somebody else had turned her into a cyborg, that she had been brainwashed to betray Captain America to the Red Skull and that she herself stopped believing to be human anymore. While Stark listened to her story he looked for a way to use her to his advantage. The LMD trusted him because she believed Steve had sent Tony to rescue her, which Tony assured her was the case (which was a lie). Tony shut off her motor functions through a chip in her neck and then revealed to the LMD that never was human at all. The LMD started to cry, which impressed Tony because it looked so real. He kept prodding while he told her everything he overheard about her before deactivating her, wiping her memory in the process. The LMD reverted to its original cube form and Stark established a neural link to turn the former Diamondback LMD into his new Iron Maniac armor, which he immediately used to break out of the Helicarrier after fighting his way through S.H.I.E.L.D. agents and the Avengers.

(Marvel Team-Up III#23/1-2) - Iron Maniac defeated Spider-Man (Peter Parker) and Wolverine (James Howlett) using the armor's shapeshifting abilities to create all the weapons he needed.

(Marvel Team-Up III#24) - Freedom Ring and Crusader (Z'reg) stopped Iron Maniac temporarily, but the armor's shapeshifting abilities gave Iron Maniac the upper hand again. The Avengers (Captain America, Luke Cage, Spider-Woman/Veranke) arrived to stop him, but Iron Maniac defeated them as well. Iron Maniac punched through the Skrull Crusader's chest and was then opposed by Freedom Ring once again. Iron Maniac used the armor to impale Freedom Ring with multiple spikes, killing him in the process, but leaving himself open for attack. Cap knocked out Iron Maniac with his shield, leaving his armor melting off of his body without Stark's mental commands to control it.

Comments: Created by Robert Kirkman (writer), Scot Eaton (pencils) & Drew Geraci (inks).

Yankee Doodle Dandy (1942) is a movie about the life of musical composer, playwright, actor, dancer and singer George M. Cohan.

It is unknown when exactly the mind of the real Diamondback was scanned, but it had to be at some point during her recovery with S.H.I.E.L.D. after her mind-controlled mind was scrambled by Citizen V (John Watkins) in Citizen V and the V-Battalion#1 (June, 2001).

The Diamondback LMD died int Marvel Team-Up III#22 and was literally turned into a mindless shell for the Iron Maniac. It ultimately ended up as goop on the streets of New York. Kirkman gave it life and Kirkman destroyed it.

Profile by Markus Raymond.

The Diamondback LMD is based on:

But should otherwise not be confused with:

images (without ads)
Captain America IV#29, p22 (main)
Captain America IV#30, p19, pan1 (head shot)
Captain America IV#31, p20, pan1 (neck broken by Red Skull)
Captain America IV#32, p15, pan1 (damaged)
Marvel Team-Up III#6, p5, pan1 (in stasis pod)
Marvel Team-Up III#22, p10, pan5 (deactivated & memory wiped)
Marvel Team-Up III#22, p12 (as Iron Maniac armor)

Captain America IV#29-32 (September-December, 2004) - Robert Kirkman (writer), Scot Eaton (pencils), Drew Geraci (inks), Tom Brevoort (editor)
Marvel Team-Up III#6 (May, 2005) - Robert Kirkman (writer), Scott Kolins (artist), Tom Brevoort (editor)
Fantastic Four: Foes#4 (June, 2005) - Robert Kirkman (writer), Cliff Rathburn (artist), Tom Brevoort (editor)
Marvel Team-Up III#13 (December, 2005) - Robert Kirkman (writer), Paco Medina (pencils), Juan Vlasco (inks), Tom Brevoort (editor)
Marvel Team-Up III#21-22 (August-September, 2006) - Robert Kirkman (writer), Andy Kuhn (artist), Aubrey Sitterson (editor)
Marvel Team-Up III#23 (October, 2006) - Robert Kirkman (writer), Roger Cruz (pencils), Victor Olazaba (inks), Aubrey Sitterson (editor)
   Story 2: Robert Kirkman (writer), Andy Kuhn (artist), Aubrey Sitterson (editor)
Marvel Team-Up III#24 (November, 2006) - Robert Kirkman (writer), Andy Kuhn (artist), Aubrey Sitterson (editor)

First Posted: 03/18/2019
Last updated: 03/18/2019

Any Additions/Corrections? please let me know.

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