While Batman has the most popular rogues gallery of DC Comics villains, none of them are as dangerous as Superman and Supergirl's Brainiac. While Kal-El and Kara Zor-El often stop him by themselves, sometimes it takes the entire Justice League to stop him. The alien collector threatens the DC multiverse on a constant basis, acting as one of its deadliest threats.
From Superman: The Animated Series to Injustice 2, Brainiac has undoubtedly earned a rank among Superman's most significant villains. However, he's gone through various interpretations. Brainiac maintains a lot of his original aspects in modern-day comics. However, before Crisis On Infinite Earths, the alien was an extremely cartoonish villain. Like most characters during DC's Silver Age, Brainiac once possessed shrinking rays, force fields, and other stereotypical science-fiction weapons.
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Brainiac's first appearance was just at the start of the Silver Age of Comic Books. In Otto Binder and Al Plastino's Action Comics #242, Brainiac reveals himself to Superman for the first time. The Man of Steel discovers Brainiac has several artifacts from Krypton, including an entire city that the Coluan shrunk before the planet's destruction. Brainiac is an alien from Colu—a world accommodating genius-level beings. Coluans rank individuals by their level of intellect, which eventually became DC Comics' primary system to rank intelligence levels for any character. For example, Krypto the Superdog would be considered a non-sentient intellectual. Jimmy Olsen, who has about average intelligence on Earth, has a 2nd-level intellect. Batman has a 6th-level intellect; this is the first rank Coluans
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