He later manages to cure Matter-Eater Lad's insanity.
Around this time, he corrects another of his mistakes by finding a way of controlling Computo.
Brainiac 5 enters a state of deep melancholy upon the thousand-year anniversary of Supergirl's death at the hands of the Anti-Monitor during Crisis on Infinite Earths and flew down to hell and finished his life.
However, as the Crisis eliminated Supergirl from existence, Brainiac 5 (as well as everyone else) has no recollection of her.
When Stargrave murders Ultra Boy's ex-girlfriend An Ryd, Brainiac 5 frames Ultra Boy for the murder.
Chameleon Boy, who suspected Brainiac 5 from the beginning, finds proof when Brainiac's madness leads him to an attempt to destroy the universe using the Miracle Machine, a device that turns thoughts into reality.
Brainiac 5's ingenuity led to the invention of, amongst other things, the Legion flight ring (perfecting an invention of the original Invisible Kid based on a metal discovered by Mon-El), the anti-lead serum that allowed Mon-El to leave the Phantom Zone and the force field belt which became the signature device of the character.
Originally, Batch SW6 appeared to be a group of teenage Legionnaire clones, created from samples apparently taken just prior to Ferro Lad's death at the hands of the Sun-Eater.Brainiac 5 is introduced in the third season of Supergirl, portrayed by Jesse Rath.He became part of the main cast in the fourth season.He successfully destroyed his creation with "an anti-matter force".Another experiment led to the transformation of fellow scientist Professor Jaxon Rugarth into the psychotic, all-powerful Infinite Man in conjunction with honorary Legionnaire Rond Vidar.