After the success of shows like Superman: The Animated Series and Batman: The Animated Series, the comic book giant and Warner Bros. knew they needed to up the stakes of this universe. At that moment, the Justice League series was born.
The hit group of heroes from DC Comics made their debut in the animated universe. Led by Superman and Batman, who were joined by Wonder Woman, Jon Stewart (Green Lantern), The Flash (Wally West), Hawkgirl, and J’onn J’onzz. Here are the ten most powerful villains on the show.
10 Thanagarians
Starting off this list is one of the big shockers of the Justice League's first series: The forces of Thanagar. The Thanagarians came to Earth under the guise of friendship and peace in an attempt to stop a galactic threat. As Hawkgirl vouched for them, everything seemed good.
However, it was revealed Earth was the Thanagar Kingdom’s next conquest, and Hawkgirl a secret agent of the Empire. Forcing the heroes to go undercover to stop the invaders, it wasn’t until Hawkgirl abandoned her people in order to save Earth that they were eventually stopped.
9 The Imperium
The first villains the Justice League faced were, in fact, the cause of the team’s formation. An army of shapeshifting, parasitic aliens, the Imperium traveled conquered various planets, they had invaded Mars centuries earlier and were frozen in place by J’onn J’onzz, the last survivor of Mars.
When astronauts from Earth accidentally released them, the invaders set their sets on Earth. Only when Batman, Superman, and the other heroes joined forces were they able to stop the planet-wide destruction and destroy the invaders once and for all, helping form the Justice League.
8 Injustice Gang
One of the League’s first battles against a team of villains was against Lex Luthor’s Injustice Gang. Comprised originally by Lex himself, the Ultra-Humanite, Copperhead, Solomon Grundy, Cheetah, Star Sapphire, and The Shade, the team proved to be an equal match for the League. However, things went downhill once The Joker forced his way onto the team.
After capturing Batman and proving his worth, the Joker caused chaos and annoyance to spread through the team. Batman was able to use his capture to manipulate members of the Injustice Gang to turn on each other, leading to the team's defeat.
7 A.M.A.Z.O.
One of the truly complex foes the League faced on the show was A.M.A.Z.O., aka the Android. Created by Professor Ivo, Lex Luthor discovered the android after the Professor passed away. Taking advantage of the android's innocent nature and the father/son relationship with Ivo, Luthor agreed to take care of the android.
Manipulating the android into attacking the League, it was able to replicate the powers of the majority of the League. However, it also gained their weaknesses, including Superman’s Kryptonite vulnerability. Ultimately, A.M.A.Z.O. discovered Luthor’s deception and left the planet.
6 Vandal Savage
One of the League’s oldest enemies from the comics made a splash in the early days of the Justice League animated series, and that enemy was none other than Vandal Savage. Originally appearing in a story in which the heroes of the League returned to find the Earth altered, and discovered Vandal Savage had traveled back in time and changed the outcome of WWII.
After traveling back to stop him and help keep the outcome of the war the way it was meant to be, Savage was revealed to be an immortal being who had influenced historical events for years.
5 Justice Lords
One of the more memorable and influential storylines in both the original Justice League and Justice League Unlimited shows involved the Justice Lords. In an alternate world, Lex Luthor became president and had The Flash executed. Angered and upset, the League went rogue and eliminated Lex, before taking over their world.
Discovering the Justice League’s universe, the Justice Lords capture and replace the League and began showcasing their unique brand of “justice.” It forced the League to work with their hated enemy Lex Luthor to strip the Justice Lords of all their powers.
4 Royal Flush Gang
One of the darker stories involved the Royal Flush Gang. Created by the Joker in an attempt to brainwash the world, he kidnapped metahuman subjects and dressed them in playing cards, then set them off to fight the League on his own televised attack.
Joker's secret weapon was Ace, a powerful metahuman who could drive anyone insane with one look. She eventually turned on the Joker and stopped the attacks; sadly, Ace's powers grew out of control and she ended up passing away in one of Justice League Unlimited's most tragic moments.
3 Legion of Doom
The greatest collection of villains to ever face the League came in the final season of Justice League Unlimited. The classic comic book supervillain league was the antithesis of the Justice League. Formed by Gorilla Grodd to expand the Secret Society, the Legion of Doom incorporated many villains from the DC Universe.
Later, Grodd was betrayed by Lex, who took leadership of the Legion in an effort to ramp up his experiments to bring Brainiac back to life. This led to a civil war in the group between Lex and Grodd.
2 Brainiac
Probably one of the greatest villains to plague the League was none other than Brainiac himself. The AI computer survived the Superman: The Animated Series and appeared on Apokolips, intent on downloading the planet’s information and then destroying it. Darkseid made a deal to lure the League to Brainiac in exchange for his planet’s protection but ultimately betrayed the AI.
While initially thought to be destroyed, Brainiac was found to be living inside the body of Lex Luthor. The two merged into one being and nearly destroyed the world. It was the Flash who unlocked his speed force powers and destroyed Brainiac.
1 Darkseid
The League's most memorable battle came against the heroes' most powerful foe, Darkseid. The leader of the hellish world of Apokolips was thought gone after his first battle with the League. After betraying Brainiac, he and Superman fought until Batman pulled Superman away in a boom tube, leaving Darkseid on the exploding Brainiac ship.
Later on, Lex accidentally brought Darkseid back to life instead of Brainiac, and Darkseid returned with some of Brainiac’s power. He nearly destroyed Earth and Superman; however, Luthor proved to be Darkseid's undoing, as the human discovered the Anti-Life Equation the latter had been searching for.