Organus

A sentient parasitic energy-leech from an unidentified part of the universe, Organus was discovered by the Legionnaires when they were called to Medicus One on an alert. Organus had been carried in his dormant form and left behind by organleggers to cover their escape. Organus uses his telepathic bedazzlement to ensnare a victim, then leeches away its life energies. If his victim has powers, he absorbs and gains those as well. He was captured when he suffered a crippling feedback reaction to Blok's inorganic structure.

-Who's Who in the Legion of Super-Heroes