While Batman, Spider-Man and the Flash are usually renowned for their rogues galleries, the villains of Superman are relatively uncelebrated. Apart from standouts like Lex Luthor, Doomsday and Brainiac, the Man of Steel doesn't have too many enemies who are well-known outside of comics-reading circles.
Despite that, the Man of Steel has a quietly impressive roster of villains, and now, we're going to take a closer look at a handful of Superman's most underrated foes. From super-geniuses and master-planners to immensely powerful physical threats, there's no shortage of villains who have it out for Superman, and each of these characters poses a unique challenge to Kal-El in one way or another.
Mongul
On paper, Mongul is a powerful foe. He’s super strong, tough, and he even possesses his own personal Death Star-like battle station, the Warworld. Mongul has definitely been a threat since he was created by Len Wein and Jim Starlin in 1980, but the alien despot often comes across as a lesser version of Darkseid.
The Watchmen creative team of Alan Moore and Dave Gibbons showed what Mongul was capable of in their seminal tales, “For the Man Who Has Everything,” which was later adapted in an episode of Justice League Unlimited. Mongul holds the dubious honor of hurting Superman and getting under his skin in a way few villains ever could. Utilizing the Black Mercy, an alien parasite, Mongul managed to put Kal-El in a dream world where Krypton never died and he had a loving wife and son. When the dream world eventually collapses, Superman is left wounded in a place even his invulnerability cannot protect: his heart. While Superman might be an unstoppable physical force, Mongul got to him through his emotions once, and there's no reason he couldn't again.
Toyman
Whereas some characters challenge Superman directly, Toyman is basically a super-intelligent mad scientist with a strong gimmick who sends his creations after the hero of Metropolis. Although he's often overshadowed by Lex Luthor, who also uses his intellect against the Man of Steel, Toyman has been underrated in a couple of key areas since he was created by Don Cameron and Ed Dobrotka in the 1940s.
Whereas Lex Luthor’s devices and schemes against Superman are more practical, Toyman is innovative and imaginative, That makes his childish persona memorably creepy, especially in moments like when he wears a doll head throughout the DC Animated Universe. Secondly, Toyman’s obsession with childhood leads him to sporadically create inventions that surprise everyone, even himself. In the Justice League Unlimited episode “Hereafter” Toyman creates an energy weapon that seemingly erases Superman from existence, but actually sends him to the future instead. While he might seem easy to write off, the sheer creativity of inventions like that prove that he's a serious threat.
Equus
Created by Brian Azzarello and Jim Lee in 2004, Equus is essentially Wolverine reconfigured into a Superman villain. As a cybernetically and genetically-spliced war machine with sharp claws, Equus is a mercenary who has found himself working for the likes of General Zod and various other shady figures.
Possessing incredible regenerative abilities, even Superman found himself challenged when the two fought. The layers upon layers of upgrades done to Equus open up countless storytelling opportunities for this villain, who has rarely appeared since the story that introduced him.
Helspont
Although he was originally created by Jim Lee and Brandon Choi as the nemesis of WildC.A.T.s in the WildStorm Universe, Helspont joined Superman's rogues gallery when that universe was folded in the DC Universe in the New 52 relaunch.
In their first meeting, Helspont quickly established himself as a foe to be reckoned with when he effortlessly backhanded Superman from Earth’s orbit to the Moon. He's a powerhouse with a slew of energy and psionic abilities, but a great deal about Helspont remains unexplored. While he's still a Daemonite alien, the history of Helspont and his species in the DC Universe is very much incomplete, and his last battle with Superman ended in a still-unfulfilled promise to return.
Mister Mxyzptlk
Hailing from the Fifth Dimension, Mister Mxyzptlk possesses nearly infinite magical powers, and he expresses them in a host of equally zany and terrifying ways. Whether he’s turning superheroes into a myriad of irritating forms or forcing them to swap bodies, the magical imp has caused mayhem around Superman's world since he was introduced in 1944 by Jerry Siegel and Joe Shuster.
Stylistically speaking, Mxyzptlk acts like an all-powerful cartoon character let loose in the real world. In addition to being one of the few foes who Superman can't defeat through brute force, Mxyzptlk is an entity that can rewrite all physical laws at a whim, and can only be defeated by saying his own name backwards. Despite his cartoony appearance, this is one of the few Superman villains who could truly defeat the Man of Steel without really trying.