Edward Beethoven Osako, called Metalhead, was a musician and a mutant in the year 2099, before Xi’an Chi Xan offered him a place on his team of X-Men. Metalhead would create music by moving through vibration-sensitive webs of sound, often amplifying and alternating the sound using his mutant power to adopt the properties of any metal he touched. He was the main entertainment at Xi’an’s Nuevo Sol gathering before Xi’an stepped to the stage to make his speech. When an assassin’s bullet wounded Xi’an, Metalhead was first to put himself in the line of fire to protect his leader. Later, he drove the X-Men out of the arcology and to safety, then joined Meanstreak and Krystalin in a raid on the Synge Corporation building to clear Xi’an’s name of the murder of their founder. But Synge’s Rat Pack captured Metalhead, along with Meanstreak, though the rest of the X-Men soon arrived to save them. They later fought their betrayer, Junkpile, along with an evolved and revived Xi’an, and soon cleared Xi’an of the charge.
When the X-Men began receiving transmissions from a woman known as Mama Hurricane, Xi’an took them to hunt her down to find out if she was the same Hurricane from the time of the Great Purge. They discovered that she was the same, but now she was the leader of a degen group called the Freakshow. After a brief fight with the Freakshow, and a talk with Mama Hurricane, the X-Men left to search for the Driver and the mutant paradise, Avalon, that she told them about. But Metalhead had been infected by the Freakshow’s Contagion, subsequently trapped in his metal form, and decided to stay behind after meeting the pregnant Rosalinda. Rosalinda still cared for Metalhead, despite his monstrous transformation, and so Metalhead joined the Freakshow at her suggestion. But her brother, Breakdown, distrusted Metalhead, and the two were constantly at odds.
The Freakshow later traveled to Oklahoma Hills, the home of the Keewazi nation, to enlist Louise Wingfoot’s help in giving birth Rosa’s baby. They were unwelcome at first, but Louise vouched for them and gave Rosa proper medical attention. Alexi Jaeger, known as Glitterspike, appeared. As the father of Rosa’s child, he claimed the baby and her mother, but Metalhead disagreed and fought him. In the struggle, Glitterspike used a mace made out of particles of light, which he was able to control, to knock out Metalhead. Glitterspike took Rosa away. But Rosa used her static interference powers to shut off his anti-grab belt, and they both crashed to the earth. A monster called the Shadow Dancer later lifted both of them and phased through its cave to deposit them in the dark. Rosa slipped away while Glitterspike attacked the creature. Metalhead, Wingfoot, and Mama Hurricane chased after the pair and found them in the Shadow Dancer’s cave. Along the way, Metalhead discovered that the blow to the head Glitterspike gave him had returned his metallic mimetic ability. They soon found Rosa and together they discovered that the Shadow Dancer was an alien creature that had crash-landed on Earth many years ago. Glitterspike attacked again, but Metalhead used the strong metal of the alien ship to stop him, and once Glitterspike’s powers disappeared due to the lack of sunlight, Metalhead beat him and left him in the cave with the alien.
Glitterspike returned much later, while Metalhead and Rosa were separated from the rest of the group. He revealed that he had finally beaten the alien, but in the process his left arm was torn off. Metalhead and Glitterspike fought again, and Glitterspike created another mace made of light to replace his entire arm. Rosa’s water broke during the fight, and she went into labor. But before Glitterspike could defeat Metalhead, the baby used its powerful mutant abilities to protect his mother and stop his violent father. Later, Rosa gave birth to her son, who was born with a radiant glow, similar to his father’s genetic enhancements.
When the X-Men and the victims of the Theatre were given Halo City as a refuge by 2099’s Doom, Metalhead and Rosa traveled there to raise Metalhead’s godson. But the Balazo Brothers, who were hijacking people traveling to Halo City, attacked on the way. Before Metalhead could stop them, Bloodhawk arrived and destroyed them. Bloodhawk then followed the pair to Halo City to help keep them and the baby safe. Though they thought that they were finally safe in Halo City, a being called Vulcann plotted to take the child, believing it to be the prophesized mutant messiah. To that end, he sent a pair of red hounds that attacked Metalhead, Sham, Rosa, and her child. Metalhead leapt on one, and together they fell out of the window. Vulcann appeared and called off the other before it could attack, then demanded the child. With no other choice, Rosa gave up her child, and Vulcann hyper-aged him into adulthood to use him against the X-Men, calling him Darkson. While the city began to flood, Rosa and Metalhead mourned the loss of her son. Rosa blamed Metalhead for taking him to Halo City. Metalhead reassured her that they were tracking the DNA of the animal that attacked him. But before they could do anything else, Vulcann appeared with Darkson at his side. At first, Rosa refused to believe that he was her son, until she saw his eyes, which were the same as hers. Metalhead attacked Darkson, but was thrown miles away, and with him gone Vulcann offered Rosa to join him. Metalhead returned to the apartment shortly afterwards, but Rosa was gone. He found both Vulcann and Rosa later, but when he attacked, Vulcann stopped him and threatened to solidify his insides until Rosa agreed to join him.
As the floodwaters began to rise, and the Darkson and Vulcann had tied the rest of the X-Men to a ship’s mast, Bloodhawk lifted Metalhead with the anchor from the destroyed Atlantean ship, and dropped him on Vulcann. Metalhead wrapped the chain around him, and dragged him down into the ocean, tying him up and leaving his godson’s captor to drown in the ocean depths. Skullfire appeared moments later, as a being of pure light, and convinced Darkson of what Vulcann had done to him. Then, along with the remaining X-Men, Metalhead, Rosa, and her confused son, traveled to the last dry piece of land on the planet, the Savage Land.