BIOGRAPHY - Page 1
Much about the man known as Caliban is a mystery, even his exact age. He was apparently an identifiable mutant from birth, as Caliban once claimed that his own father named him after the monstrous character from Shakespeare’s “The Tempest” due to his harsh features. What happened to his parents is unknown, but eventually Caliban left home and created a new life for himself underground in the tunnels beneath Manhattan, New York. [Uncanny X-Men (1st series) #148]
[Note: Against his earlier statement, Caliban mentions in Uncanny X-Men (1st series) #294 that he had a different name before he became a Morlock, and that it was Callisto’s idea to call him “Caliban”.]
At some point, Caliban encountered another mutant outcast living in the tunnels, a woman named Callisto. She helped him cultivate his mutant detection power in order to seek out others of their "strangeborn" kind. Along with Sunder and Masque, the four of them became the first, but hardly the last, Morlocks. [Uncanny X-Men (1st series) #176] Soon the newly christened "Alley," an abandoned underground bomb shelter constructed under Manhattan during the Cold War, was
filled with dozens, even hundreds of mutants and other outcasts, carving out an entire civilization for themselves underneath the bedrock. Despite his status as a founder of this community, Caliban remained an outsider among the Morlocks, perhaps because he was much more peaceful than the other founding Morlocks. He began to live a bit apart from them and his loneliness grew. Caliban spent quite some time living in the tunnels, possibly years, long enough that he forgot what the sun felt like on his skin.
Eventually, Caliban drew close enough to the surface that his mutant detection power alerted him to the presence of Kitty Pryde and Storm, attending a concert by their friend Dazzler at the Infinity nightclub. Sensing others like 
him close by, Caliban fixated on the idea of meeting these "others" and ending his loneliness. Entering the club, Caliban encountered Kitty Pryde first and instantly became enamored with the "Sprite-child." As she fainted in his arms, Caliban was confronted by Storm and Spider-Woman, who mistook his intentions as hostile and threatened the sewer-dweller with violence. Frightened by their attack, Caliban struck back and attempted to flee to the sewers with his new "friend." The super-women caught him before he reached the tunnels, however, and recovered Sprite. Caliban calmed down enough to explain he only acted out of loneliness, not malice. Though they offered him a place at Xavier’s school, he left Kitty Pryde and the others in peace. [Uncanny X-Men (1st series) #148]
[Note: Caliban's statements in Uncanny X-Men (1st series) #148 make it seem as if he had been living underground in absolute solitude for years, which doesn’t fit later published stories about the Morlocks. Going by their large number and the complex set of laws and social norms they developed, the underground society of mutants must have been in existence for years. As one of their founders, Caliban must have been part of them from day one.]
Back in his underground home, Caliban couldn’t forget Kitty Pryde and longed to see her again. When she and the X-Men investigated Callisto's kidnapping the Angel, Caliban stumbled across Kitty in the tunnels, 
violently ill after an encounter with the Morlock called Plague. He took her back to his personal quarters, in the hopes that Kitty would stay with him forever after he nursed her back to health. Although she was extremely weak with fever, Kitty knew her friends were in trouble, and begged Caliban to help them. She promised to stay with him underground if he aided the X-Men in their conflict with Callisto. Though he was not a fighter, Caliban did help the X-Men by informing them that Morlock law allowed for a trial by combat to countermand Callisto's rule. As a result, Storm challenged Callisto and won leadership over the Morlocks, as well as safe passage back to the mansion, where Kitty's illness was properly treated. [Uncanny X-Men (1st series) #169-170]
Despite her promise, Kitty Pryde did not return to Caliban after she recovered, leaving him distraught and more lonely than ever before. Callisto used this to her advantage, striking back at Storm by kidnapping Kitty and forcing her to fulfill her promise to Caliban. Initially horrified at the idea, Kitty ultimately relented to carrying out her promise after the Morlock Healer helped restore
Colossus from a state of near-death. Despite her acquiescence, however, Caliban realized how wrong it would be to force her to stay with him, and released Kitty from her vow. The two parted as friends and Caliban gave her his "wedding present" - a single red rose to remember him by. [Uncanny X-Men (1st series) #176, 178-179]
As the X-Men and Morlocks formed a stronger alliance between them, Caliban worked with the X-Men on several occasions. For instance, when the Hellfire Club was hunting their missing member, Rachel Summers, Caliban helped the X-Men to locate her. [Uncanny X-Men (1st series) #208-209]
Sometime later, Caliban and the young Morlock named Leech met one of X-Factor’s young charges, the mute mutant Artie Maddicks. Artie had wandered down into the Alley to search for his missing friend, Rusty Collins. Caliban and the two boys soon found themselves in a fight to stay alive, as the Marauders had come to the Morlock Tunnels to slaughter every Morlock they found on behalf of their mysterious master, Mister Sinister. During their attempt to escape with their lives, Caliban's chest was sliced open by the Marauder named Sabretooth. Fortunately, Leech managed to drag him to safety, namely a pipe too narrow for Sabretooth to fit in and follow. [X-Factor (1st series) #10]
The Marauders were chased off by Power Pack and X-Factor, who had ventured into the tunnels to save their friends. Beast and Iceman brought the injured Caliban and several other Morlocks back to X-Factor’s headquarters for protection and medical attention. Caliban was deeply pained by the deaths of his people, as his mutant ability to sense his fellow mutants made him keenly aware that the Alley was now totally devoid of mutant life. [X-Factor (1st series) #11]
His growing thirst for vengeance made Caliban a harder, more aggressive person. When Masque, one of X-Factor's more violent Morlock guests, attacked their hosts Beast and Boom-Boom, Caliban challenged him and fought Masque in a brief trial by combat. He managed to physically best the crazed mutant and forced him to undo the effects of his face-shifting power. [X-Factor (1st series) #15]
After he helped the other Morlocks reestablish their homes in the Alley, Caliban and Leech returned to X-Factor to help them and repay the debt of kindness they had shown him. Caliban immediately proved his usefulness when X-Factor received a terrorist warning about a mutant named Rictor, who was planning on leveling San Francisco with a powerful earthquake. Flying to California in the mutant freedom fighter personas as the X-Terminators, X-Factor gave Caliban a personalized uniform and officially accepted him as a member of the team. After Caliban pinpointed Rictor's mutant energy in a particular building, the X-Terminators stormed the location only to find that Rictor was an innocent teenage mutant who had been unwillingly turned into a weapon by the group known as the Right, in an effort to stir up anti-mutant hysteria at the cost of innocent lives. [X-Factor (1st series) #17]
Although he cherished being an active part of the team, Caliban deeply regretted his uselessness in battle. His mutant detection power was entirely passive and his other powers of strength and fear 
were irregular, arising only when his adrenaline levels rose and totally beyond his control. Though he received some hand-to-hand combat training, even those skills proved worthless against the heavily armored Right mercenaries when they invaded the X-Factor complex. The Right stormed Caliban's new home, kidnapped his friends, and cast him aside as if he were nothing after hitting him with a near lethal dose of tranquilizer darts. This incident only furthered Caliban's feelings of antipathy towards normal humankind, his own uselessness and his continuing need for revenge against those who had harmed him and his people. Unfortunately, the other members of X-Factor were too caught up in their own problems to recognize the growing resentment in Caliban's every word. [X-Factor (1st series) #21-22]
Right after rescuing their charges from The Right in Arlington, Virginia, X-Factor was teleported into the presence of the Horsemen's commander, Apocalypse himself. 
While X-Factor fought the Horsemen, Caliban could do nothing and was once again cast aside early on during the battle and completely forgotten by both sides. After Apocalypse imprisoned the other members of X-Factor and forced them to watch as he sent his Horsemen to attack Manhattan, Caliban had the opportunity to free his teammates while the villain's back was turned. Instead, consumed by his desire for vengeance against the Marauders, Caliban announced himself to Apocalypse and pledged to serve the Eternal One as his Hellhound, if Apocalypse would increase his powers as he had done for his Horsemen. [X-Factor (1st series) #24-25]