Brainiac

Brainiac is a super-intelligent extraterrestrial being who travels the universe, collecting knowledge and shrinking cities to add to his collection. His obsession with knowledge often leads him to clash with Superman, as he seeks to conquer Earth and eliminate its heroes. Over the years, Brainiac has undergone various transformations and has been depicted as both a robotic entity and a humanoid alien, solidifying his status as one of Superman's greatest adversaries.

A highly intelligent alien android and one of Superman's most formidable foes, known for shrinking cities and collecting knowledge.