Top 10 Best Power Rangers Villains

Lord Zedd (Mighty Morphin Power Rangers)

Though he was dumbed down into a pathetic joke after they made him marry Rita because snowflake parents thought he was too scary, Zedd was an impressive villain throughout most of Season 2. It looks like the writers of the comics know that because they're taking the series in a new direction to avoid that mistake.
Though it happened only once, he's also the first lead villain to take on a Ranger in person. Too bad it didn't happen more often. Power Rangers Annual #1 showed some interesting insights into him, revealing that trying to take the Zeo crystal reduced him to his current form. I'd like to see the story behind that - it makes him even more interesting as a character.

The Psycho Rangers (Power Rangers in Space)

These were badass! The hardest fight any Ranger had to battle took them many episodes to be defeated.

Astronema (Power Rangers in Space)

Not only the hottest villain, but she had the best story.

Ransik (Power Rangers Time Force)

He was a tragic villain but also a ruthless crime lord who nearly defeated the Time Force Rangers, but turned himself in after nearly killing his daughter Nadira by accident.

This guy was ruthless and cruel, but not totally evil. Rejection is what drove him to hate mankind. It's unclear whether he had and lost a wife or if he simply raised Nadira as his own, but that would be an interesting story one day.
He also faced the Rangers in person quite often, unlike most lead villains who prefer to send their creatures and watch from behind a safety line.
Unlike most Ranger arch-villains, he sees the error of his ways and gives himself up in the end. This provided the American series with a much more interesting foe than the Japanese version. He also redeems himself in the Wild Force guest appearance and is turned human. Ransik is one of the few villains to have a happy ending.

Trakeena (Power Rangers Lost Galaxy)

Trakeena had a huge story arc. She embraced her evil.
It is said that her evil green monster form is so powerful that Olympius and Queen Bansheera would have been killed by her. Queen Bansheera herself stated that.

Trakeena was the most powerful of the old series. She had more fighting scenes than Rita, Zedd, Divatox (of course), King Mondo, etc., and more powers than Astronema.

Ecliptor (Power Rangers in Space)

Screw the idea of letting Divatox and Lord Zedd survive! Ecliptor was much more deserving of a second chance!

Not only the coolest-looking villain/general, but the most tragic one as well since he undeservedly died.

Mesogog (Power Rangers Dino Thunder)

Probably one of the most evil Ranger foes ever. He wants to return the world to the Jurassic era and is willing to destroy all of humanity to achieve it. Unlike most Ranger villains, he doesn't surround himself with any imbecilic comic relief. He obviously has no tolerance for such things, and good for him - those dim-witted lackeys are usually more annoying than funny.
His human persona as Mercer is a lot like The Green Goblin - a wealthy man driven against his will to become an insane monster. Mesogog is almost on equal ground with Lord Zedd as the most powerful evil encountered by a Ranger.

For some reason, I have always liked this villain because he reminded me of times when Power Rangers was not ruled by the horrible corporate company Nick. He was an overall great and terrifying villain. Him and the legendary Ranger Tommy Oliver's return is what made Dino Thunder one of the best modern Power Ranger series ever.

Rita Repulsa (Mighty Morphin Power Rangers)

She was the original Power Rangers villain who brainwashed Tommy to be her evil Green Ranger and used him to nearly destroy the Rangers.

She was the most smart and scheming villain in all the Power Rangers series. She created the Green Ranger and Kat. She has a sense of humor and even outwitted Zedd.

She is the coolest villain in any Power Rangers series. She created the evil Green Ranger, and she is the one who trapped Zordon in the capsule. So wicked!

Darkonda (Power Rangers in Space)

He is so evil that he always looks for ways to defeat the Rangers, Astronema, Ecliptor, and Dark Specter.

Divatox (Power Rangers Turbo)

First and only villain to defeat and destroy the Rangers' power and still be good. Kind of sexy and such a diva. Great character.

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Bajillia Naire (Power Rangers Cosmic Fury)

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Nayzor (Power Rangers Wild Force)

Goldar (Mighty Morphin Power Rangers)

Goldar is like Shredder was to Krang - the one who did the dirty work. He took on the Rangers on more occasions than any other enemy. In some ways, he could have been a bigger threat if he had been in charge, but he was a warrior who existed to take orders rather than give them.
His loyalty instantly shifted to Zedd, and he seemed thrilled to have him take over. Probably because he felt he could easily destroy the Rangers. However, MMPR Annual #1 also shows that his loyalty goes to whoever is most powerful.
Goldar's fate was never totally clear at the end of the In Space series. Most villains were either destroyed or turned into normal humans, but who knows? He was a lot more resourceful than most gave him credit for. He may still be out there, waiting for the time to make his next great conquest.

Lothor (Power Rangers Ninja Storm)

Master Org (Power Rangers Wild Force)

Ivan Ooze (Mighty Morphin Power Rangers: The Movie)

He scared me, but I loved him. Does anyone else look at him and see Satan?

Evil Green Ranger (Mighty Morphin Power Rangers)

He was capable of defeating all five MMPR Rangers at once, and he nearly destroyed the Rangers while under Rita's spell.

Yes, the very first evil Power Ranger, and later became an official Ranger.

Zen-Aku (Power Rangers Wild Force)

I really think Zen Aku should be number one. Name another villain we all were rooting for instead of the Power Rangers. Not only that, search up "The Theme of Zen Aku."

Dude, he is the most powerful one EVER! He stole almost all the Wild Force Zords.

Sorry, just look at the guy - he's a badass who can take all the Rangers on at once.

Camille (Power Rangers Jungle Fury)

Venjix (Power Rangers RPM)

Venjix conquered the world except for one city! That's better than all the other villains. He even made people into hybrids to help him!

Anyone notice how the first Venjix was the main General in Forever Red in Wild Force?

Tenaya 7 (Power Rangers RPM)

Rito Revolto (Mighty Morphin Power Rangers)

Frax (Power Rangers Time Force)

Frax hates humans and mutants. Though he's with Ransik most of the time, he always has his own agenda and will double-cross Ransik to achieve it.
After going out on his own, Frax becomes even more dangerous. He becomes a third faction in what's now a three-way war.

Deviot (Power Rangers Lost Galaxy)

Vrak (Power Rangers Megaforce)

He seems like a jerk, but behind every jerk, there's a reason.
I believe that since his father obviously pampered and spoiled Vekar, Vrak grew jealous of him. Maybe that's why he acted that way. He's also really intelligent.

He's so tough, taking Orion's life (well, most of it) and kidnapping Robo Knight. He actually almost destroyed the Earth.

King Mondo (Power Rangers Zeo)

Unlike Zedd, marriage didn't dumb him down. But then, his wife actually loved him and supported his acts. He also grew himself twice to fight the Rangers.
He's not exactly built for hand-to-hand combat, but he's proven himself very powerful as an individual.
Unlike the American version, though, in the original Japanese series he was destroyed for good and didn't come back like here. His son Sprocket grew into Gasket, who here was an entirely different character, and took over in his father's place for the remainder.
Mondo commanded great respect from those who served under him. In Wild Force's "Forever Red" episode, what was left of his Empire vowed to avenge him. He had a great deal of loyalty, as his final underlings went down still in service to their king.

Sledge (Power Rangers Dino Charge)

Sledge is intelligent and devises plans like a general. He is powerful enough to defeat the Rangers.