2) HALK-KAR
Last son of the planet Thoron, Halk-Kar crashed on Earth fully powered, causing Superman to wonder if Halk might actually be a lost big brother. After a few unsuccessful attempts to work as a team, Halk and Kal realizes that Halk is not a Kryptonian at all, but is instead an astronaut who landed on Krypton, encountered Jor-El and moved on with just enough evidence on his person to fool Superman into thinking them related, leading to shenanigans and a twist ending…
If this all sounds familiar, it’s because the story was repurposed some eight years later to debut Legionnaire Mon-El. (Officially, Halk’s encounter with Kal-El took place on Earth-Two, Mon’s on Earth-1.)