Dr. Jonothon Cayre was an enemy of Excalibur.
In America, Dr. Cayre witnessed a battle between Thor and the Air-Walker android.
Though the Air-Walker android was temporarily destroyed, Cayre got his hands on a small piece of the alien android, which was equipped with self-generation technology.
Cayre worked with Machinesmith, who gave him a Life Model Decoy (LMD), which Cayre used as his assistant, Norm.
Cayre developed a prototype of the Air-Walker and then eventually rebuilt the android itself with the aid of Norm the LMD.
Cayre attempted to apply Galactus' self-regeneration technology to human physiology. He experimented on himself and was killed by the process. However, the technology then resurrected him, then killed him again, then resurrected him again, etc. He was hideously mutated and driven completely insane as a result.
Cayre and the Air-Walker android began to rampage, slaughtering the entire fishing village of Carrin's Hollow. Many were murdered outright by the android, while the survivors were reduced to nerveless protoplasm by Cayre. They then split up and began roaming the Scottish countryside outside of Glasgow.
In addition, Norm the LMD, who contained a nuclear warhead, went missing.
Brigadier Alysande Stuart of WHO sent Excalibur to stop the madness: Nightcrawler was sent to track down Norm the LMD; Shadowcat to investigate Cayre's underground vault to locate the Air-Walker prototype; Meggan to Cayre's laboratory to destroy it via SHIELD hardware; Phoenix to stop Cayre himself; and Captain Britain to dismantle the Air-Walker.
At Cayre's laboratory, Meggan encountered Coldblood-7, who had been sent there by Roxxon Oil Company to obtain a bio-weapon present there. After a short struggle, Meggan revealed to Coldblood that the weapon could turn humans into nerveless protoplasm. Agreeing that the weapon was too dangerous, Coldblood reneged on his first contract, destroying Cayre's laboratory and inducing a virus into his computers to destroy all of his notes.
Cayre stopped at Clover's Pub in Clover's Corner, twelve miles up coast of Carrin's Hollow.
Phoenix tracked Cayre to Clover's Pub and confronted him. He transformed the other pub-goers into nerveless protoplasm and then assaulted Phoenix, who formed a protective shield that kept him out. Cayre continually repaired himself as Phoenix injured him, and—as he was preparing to leave to use his power on others—Phoenix debated using her full power to scatter his molecules from one end of the universe to the other. Seeking another alternative, Phoenix instead fused some glass into an airtight chrysalis around Cayre. Without oxygen, Cayre knew he would suffocate and be resurrected only to suffocate again, etc., but Phoenix hoped that the WHO Technicians who arrived to take him away could find the means to cure him.
Captain Britain battled the Air-Walker android, crossing the opposite sides of his cosmic energy-collecting Fire-Cloak, which caused a feedback loop that destroyed the Air-Walker android.
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