Actually, Command Kid wasn't a reject - he was actually accepted into the Legion thanks to his illusion-casting powers (ADV #328, 1965). Turns out, however, that he only had these powers because he had been possessed by a demon, and said demon then tried to destroy the Legionnaire's powers until it was exorcized by its only weakness - gold (like silver is anathema to certain supernatural creatures). Element Lad did the honours, naturally. Once the demon left, presumably the host lost the powers and left the Legion.