The first Invisible Kid was Lyle Norg, an early member of the Legion who gained his powers from a chemical serum he invented. He first appeared in Action Comics #267. His scientific aptitude meant he got along well with the super-intelligent Brainiac 5. His abilities made him a valuable asset to the Legion Espionage Squad, of which he was a permanent member. Norg also served one term as Legion Leader. He was killed by the monster Validus of the Fatal Five in Superboy and the Legion of Super-Heroes #203 (July/August 1974).
The original BG was done by Sabra Haskell, I changed it a bit to go with Invisible Kid.
I'm currently working on some more Legionnaires, I think I'm almost half way done with my list.
Any character you would like to see?