Halk Kar and SupermanMon-El / Lar Gand is long running member of the Legion of Super Heroes. However, the story he first appeared in was a recycled from another story. The original story is the Superman # 80 story "Superman's Big Brother", the only appearance of Halk Kar.
An amnesic Halk Kar crashed landed on Earth and was found by Superman. Due to a note by Jor-El being in the rocket, Superman assumed Halk Kar must be his older brother (despite having a different last name). Superman discovered, while Halk Kar had most of Superman's powers, Halk Kar's powers were weaker than his. Superman decided to use his powers to make Halk seem more powerful to save him from the humiliation of having a younger brother stronger than him. Halk Kar gained a superiority complex and started to trying to date Lois Lane. Halk Kar's memory returned. It turned out he is the from the planet Thoron (which is in the same solar system as Krypton). He accidentally crashed on Krypton before its destruction and Jor-El sent him to Earth (which brings up the question why Jor-El didn't just sent him back to Thoron).
In then-present day, Halk Kar returned home after he got his ship repaired.
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