Angel and Iceman are furious that the Professor has disallowed them to join Cyclops and Beast in battling Grotesk. When they present their displeasure to Jean, she refuses to allow them to go. When the Professor finally exits his study, the other X-Men demand that the Professor let them go, and Charles once more refuses, telling Marvel Girl not to allow them to leave.
While deep below New York City, Cyclops and Beast fight Grotesk and during the fight, one of Scott's optic blasts strikes a machine that causes the cavern to fill with radioactive fog. Detecting the Professor attempting to probe his mind, Grotesk believes that it is Xavier who is responsible for the earth tremors that destroyed his kingdom and he departs to track Charles down. When Cyclops attempts to follow Grotesk through the fog, the Beast pulls him back and warns him against entering the lethal cloud.

When Cyclops and Beast return to the mansion, they also try to seek an audience with the Professor but Jean keeps them at bay, even going so far as to use her telekinetic powers to keep her teammates away. She then tells the X-Men that she has received a mental command from the Professor (the others are upset that they did not receive it also) to come to the Professor's aid.

Grotesk meanwhile has smashed his way into the lab where he has detected the Professor's mental probes and finds what he thinks is the device causing the earthquakes and Dr. Hunt. Throwing Hunt aside to destroy the machine, "Hunt" takes off a fake mask to reveal that he is really Professor X. With the machine attempting to save the world from the earthquakes, and Grotesk's possible tampering likely to cause the destruction of mankind, the Professor keeps Grotesk stunned with his mental powers until the other X-Men arrive. However, not before Grotesk can start the device to send vibrations into the Earth's core.
Angel is the first to arrive with mirrors to reflect light into the light sensitive cavern dwellers eyes. As Cyclops, Beast, Angel and Iceman fight Grotesk, Marvel Girl is ordered to stop the machine, but finds that the lever is jammed in position. As the battle rages, the Professor and Marvel Girl combine their mental powers to bombard the machine, causing its effects on the Earth to slow down. However they are not slowing down fast enough and the Professor (telling Jean to stay back) gets closer to the machine to affect it more effectively. Meanwhile, Grotesk throws Angel into the other X-Men allowing him a chance to break away from the fight and to try to speed up the process of the machine. Pushing the Professor aside, Grotesk slams his fist into the machine. Instead of causing it to complete its job, it instead explodes seemingly killing Grotesk.
Checking the rubble, the X-Men find that their victory has come at a cost; the Professor has been mortally wounded. With his dying words, the Professor explains Grotesk's story, and confesses to his students that he himself was dying of a fatal illness and hence his secrecy. The Professor then passes away, and although the X-Men have saved the Earth they have suffered a most tragic loss.

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