Source: anguerde.com

2. Brainiac

Vril Dox, aka Brainiac, was a native of Colu, a planet that prioritized intelligence above all else.

He liked collecting things. Specifically, he liked to shrink down cities into little bottles and keep them. As someone with a deep love of miniatures, y'know I get it. I understand where you're coming from, Brainiac. Over the years, Brainiac sent numerous robot duplicates in his place to Earth and throughout the cosmos, including the terminator-esque Brainiac 2.5 and the crazy-awesome Brainiac 13.

Hey. DC Rebirth. Bring back the Brainiac 13 design. I prefer "ultimate robot emperor lord" over "green-skinned dude" any day of the week. But Brainiac was awesome for one primary reason: He was smart as hell. He was capable of creating vast and terrifying devices for torture, murder, and everything in between.

And the only person on earth capable of taking him down was Superman himself. Which he usually did by smashing robots.