Professor X, Angel, Cyclops, and Marvel Girl have all been defeated by Magneto, who put the team into a high altitude hot-air balloon, hoping that his hated foes would perish once it reaches its destination of 1,000,000 feet. Magneto revels over the victory, magnetically lifting the mansion out of its foundation and causing it to crash down on the ground. Entering the residence of his hated foes, he then uses his magnetic powers to destroy Cerebro. However, his destruction is interrupted when the Worthingtons -- Warren's parents -- arrive for a visit. Magneto confronts them at the front door, and uses magnetic hypnotism to put them under his thrall, and orders them to go sleep upstairs in the upper bedrooms. Megneto then comes to realize that one of the X-Men -- Iceman -- is missing, and waits for him to return to the mansion so that his revenge can be complete. Magneto boasts how Iceman is the weakest of all the X-Men.
Iceman, meanwhile, is still recovering from injuries sustained battling the Sentinels. His doctor injects the unconscious Mutant with a new medicine with a special device. It stops the boy's delirious rantings; however, if he will awaken remains to be seen. Meanwhile, high above in the weather balloon that might mean their doom, Professor X exerts all his mental power to try and overload the mental-wave disruptor that has been attached to his head. His ploy succeeds and he revives the rest of the X-Men, and they begin to assess their abysmal situation, and wonder how Magneto could have returned, after being taken from Earth by the Stranger.
Back at the X-Mansion, Magneto uses his magnetic powers to assist him in constructing a device that can duplicate body cells and create an army of mutant clones, using the Worthingtons as the source material. Probing the situation mentally, the Professor learns of Magneto's plans and tries to revive Iceman, who awakens from his coma and agrees to go out and try and stop Magneto. Marvel Girl is then instructed to use her telekinetic powers as an anchor, preventing their balloon floating up any higher. The Professor then probes Magneto's mind so that he and the X-Men can learn how Magneto managed to return to Earth:
They discover that shortly after Magneto and Toad were taken to the Stranger's homeworld, Magneto began plotting his escape. One day they were left to their own devices, and Magneto -- taking advantage of the fact that the Stranger allowed them to roam his planet freely -- brought Toad to a location where a number of rocket ships had been collected by the Stranger and put on display in a museum. Magneto then used his magnetic powers to gain access to one of the rockets, and after kicking Toad off the entrance ladder, Magneto flew the rocket back to Earth.
Bobby arrives at the Mansion and spies on Magneto to learn what his plan is. Seeing Magneto creating Mutant clones from the Worthingtons DNA, Iceman sneaks into the room where they are sleeping and uses his ice powers to stop the flow of information, leaving the clones inert. Furious that his creations have not come to life, Magneto enters the room and attacks Iceman. Magneto underestimates Iceman's ability, and Bobby manages to fight off Magneto's attacks, and create an ice slide to send the two of them out of the mansion.
Meanwhile, aboard the balloon, the Professor comes up with a solution to get them out of the basket. He orders Cyclops to use his optic blast to poke a minute hole in the balloon so that the helium inside slowly leaks out and they can then safely descend to the ground below. The X-Men safely land on the ground and attack Magneto together, however the Master of Magnetism manages to fight them off. Before they can renew their attack, Magneto magnetically traps Iceman and threatens to kill him if the X-Men don't cease their fighting. Iceman tells the others not to surrender for him, however Angel flies in and manages to pull him free from Magneto's grasp.

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