Bates, Swan and Chiaramonte conclude the Vartox story in Superman 357 (March 1981).
Although the story begins with Superman imprisoned by the Tynolians, this is exactly where he wants to be. Vartox is kept busy by threats they manufacture, while Superman spies on the leadership of the world He discovers that they have plans to sacrifice the heroes to an alien creature called Moxumbra, which the people treat like a god.
Superman gets put into a capsule by the Tynolians, who have a sort of super-chanting power that keeps him passive. They shoot him out to Moxumbra, but really he is simply bait for Vartox, the one they truly want to send as dinner.
Together, the heroes destroy Moxumbra. To Superman’s surprise, Vartox chooses to stay on the planet. With Moxumbra gone, the Tynolians chanting power is gone, but they are also no longer under the mental domination of the monster, and now truly do need a hero.
Vartox returns the following year.
Superman 2020 is back for a one-shot story, in which he establishes a new identity, thanks to Rozakis, Denys Cowan and Joe Giella. Perhaps it’s Giella’s inks, but it’s impossible to see Cowan in this art.
He has adopted the name John Hudson, and works as an air traffic controller. We also meet his romantic interest, Melodee Sellers, his supervisor.
He spends much of the story trying to figure who or what is behind the sudden failures of solar batteries across the city, only to discover that it is his fault. His super-speed had been damaging the dome over the city, which in turn affected the batteries.
I bet he didn’t tell his parents about this case.