Supergirl debuted in 2015 with a quintessential comic book formula—there was a villain-of-the-week who was conveniently defeated in one episode by Kara Danvers/Supergirl (Melissa Benoist) and her allies. Meanwhile, an overarching season villain would play the long game and face-off against the heroes in each season finale.

With the final half of Supergirl’s final season coming up, we take a look back at some of the best villains on the show. This show has plenty of merits, and the villains are a big part of the show’s appeal.

Most of these villains had multi-episode arcs; some even had multi-season arcs. These nine characters challenged the Girl of Steel and her Super-friends, and they were entertaining while they did it.

9. Indigo

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Image via The CW

Indigo/Braniac 8 (Laura Vandervoort), an alien android cyberterrorist, was a force to be reckoned with in Season 1 of Supergirl. She was a Fort Rozz resident, aka, an inmate in the Kryptonian maximum security prison. She was a baddie even before she reached Earth – Indigo had set several inmates free and they were roaming around Earth, terrorizing people.

As a villain, Indigo made things difficult for Supergirl and the team. She was super-smart and had the ability to transport herself over the internet. She wanted aliens to take over Earth and was pretty close to succeeding in her goals. At one point, Indigo even got her hands on some nuclear missiles to blow up the planet.

Aside from her super-strength and digital skills, Indigo was also a master manipulator. She knew how to get under people’s skin by taunting them about what they’d lost—be they friend or foe. Indigo deserved to be a multi-season villain, but unfortunately, she only lasted half a season.

8. Queen Rhea

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Queen Rhea (Teri Hatcher) was the mother of Mon-El (Chris Wood), the one-season boyfriend of Supergirl. Mon-El believed his parents and people had been killed when his home planet Daxam, like Krypton, was destroyed, but he found out that none of that was true.

Rhea’s conflicts with Supergirl began when her lack of morality and her lust for killing became obvious. Rhea was also very attached to her son and wanted him to return home instead of staying on Earth. Rhea’s villainy was such an old-fashioned mother-in-law from hell—or, from Daxam—storyline. You can’t help but love Hatcher’s incendiary performance as the overbearing alien mom.

To stop Rhea, Supergirl’s team had to disperse lead in the air, but that meant none of the Daxamites could survive, including Mon-El. Because of Rhea, Mon-El fled Earth and had to leave Kara. He may not have been the best boyfriend for Supergirl, but we’re not going to forgive the Queen for breaking Kara’s heart.

7. Astra In-Ze

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Families can be the worst. Mon-El wasn’t the only one with evil relatives — Kara had to deal with an evil aunt. General Astra In-Ze (Laura Benanti) was a Kryptonian terrorist sentenced to serve a life term in Fort Rozz after murdering several innocents prior to Krypton’s demise. Luckily for her, this sentencing saved her from her planet’s destruction. However, Astra wanted vengeance against the person who arrested her — her identical twin sister Alura (Benanti), mother of Kara Zor-El.

Since Alura was dead, Astra turned her sights on Kara and all of planet Earth. What made her especially evil was that Astra and Kara were very close on Krypton, but Astra decided against rekindling their bond. Instead, she and her malicious husband, Non (Chris Vance), attempted to force Kara into ruling Earth with Astra. When that failed, they tried to kill Kara and her family.

Astra was unstoppable at times, bouncing back from every defeat. Eventually, though, she lost control of her husband, before being killed in battle.

6. Maxwell Lord

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What can we say about Maxwell Lord (Peter Facinelli)? He was a self-made billionaire, starting up Lord Technologies with his inventions. Unfortunately, he had a grudge against Supergirl, eventually becoming obsessed with seeking out her true identity. He even created a clone of Supergirl, Bizarro, to try and take her down.

Maxwell was smart—he was able to deduce Supergirl’s identity through his reverse-interrogation of Alex, but eventually, that proved to be useless to him.

Maxwell’s unpredictability made him a compelling character, not just a great villain. He had surprising chemistry with Alex Danvers, which made us hope for his redemption. Maxwell became an occasional ally to Supergirl, though his plans often backfired, like the time he created Red Kryptonite that ended up turning Supergirl evil. Unfortunately, his moral ambiguity and distrust of Supergirl put him at odds with the good guys. He would have made an excellent recurring guest star, but the character never returned after Season 1.

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5. Reign

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Image via The CW

Reign was a Kryptonian world killer who arrived on Earth due to the same catastrophic events that sent both Kal-El and Kara Zor-El to the planet. But, unlike the superheroes, Reign’s consciousness was buried and she instead grew up believing she was a regular human named Samantha Arias (Odette Annable).

Sam was a single mom who loved her daughter but had a strained relationship with her own (adoptive) mother. When she arrived in National City, Sam became fast friends with Kara and Lena Luthor (Katie McGrath). Meanwhile, Reign was the violent harbinger of the End of Days.

The dichotomy of the loving friend versus the world-ending villain worked hand-in-hand as Sam’s emotions fueled Reign’s emergence—at one point, when Lena was almost killed, Sam’s anger led to Reign attacking the killer.

The dual personality of Sam and Reign made the character a compelling addition to the show. Annable balanced Sam’s earnest love for her daughter and her friends with Reign’s cold determination to bring this character to life.

4. Lillian Luthor

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With the appearance of her children, Lena and Lex Luthor (Jon Cryer), one tends to forget what a powerful and evil villain Lillian Luthor (Brenda Strong) has been. She may have been playing second-fiddle to Lex in later seasons, but Lillian was once the leader of Project Cadmus, an organization that experimented on aliens, in part out of her hatred for Superman defeating her son and humiliating her family.

Lillian successfully captured Supergirl and her boyfriend Mon-El, had her own pet Superman — Cyborg-Superman — at her beck and call, and she has been duplicitous at every turn. Lillian is a bad itch that you can’t scratch, and she’s always around to torment poor Lena, who is the only redeeming part of the Luthor line.

Strong’s ability to play Lillian as both irredeemable yet compelling has made this character one of the most memorable additions to the show.

3. Manchester Black

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Manchester Black (David Ajala) was an incredibly layered character, who deserved more screen time than he got. He debuted on Supergirl Season 4, which was a season packed with storylines and characters, and Black was sidelined for a large part of it.

While Manchester Black had a troubled and violent past, he had put it behind him thanks to his savior and fiancée, Fiona (Tiya Sircar). He was embracing a non-violent future when Fiona was killed by the alien hate group the Children of Liberty, thereby setting him on a path to anger and vengeance.

Ajala brought a lot of depth to the character. You could tell that Black was a man who was desperate to enjoy a new and happy life, before it was stolen from him. It’s a real shame that Black ended up being morally opposed to J'onn J'onzz/Martian Manhunter (David Harewood), because the two of them made quite the team when they were searching for Fiona.

2. Agent Liberty

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Image via The CW

The Supergirl showrunners knew what they were doing when they debuted Sam Witwer’s Ben Lockwood/Agent Liberty. The writing showcased how Lockwood twisted his personal misfortunes into a campaign against the aliens on Earth. This was a villain of the times—a xenophobic hatemonger whose speeches and actions echoed those of the unfortunate reality of 2018 America.

Witwer played this character with aplomb. You could feel Lockwood’s hate bubbling beneath the surface, but the villain was never a caricature. This was a man who had suffered greatly, but instead of grieving his losses and being accountable, he blamed those who were different—on the show, these were aliens. Lockwood used real fears to turn people against Supergirl, and people like her. His every scene was a stark reminder of the horrors of the real world.

Agent Liberty would have effortlessly made it to the top of this list, but there was one villain who was just that much smarter than him.

1. Lex Luthor

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Remember the time when Jon Cryer’s casting as Lex Luthor filled us with trepidation? He put those fears to rest from the get-go. Supergirl often recasts actors from previous DC adaptations, and Cryer was no different. He’d played the comical Lenny Luthor, Lex’s nephew, way back in 1987’s Superman IV: The Quest for Peace, but his return to the live-action DC universe was very different.

Cryer plays the DC supervillain with smarm and charm, firmly placing his comedic nice guy persona on the backburner. His take on Lex is equal parts restrained and larger-than-life. Lex on Supergirl exudes arrogance, and thanks to some smart writing, it’s easy to understand why Lex has a God Complex.

Lex in the comics has always been several steps ahead of everyone, and this version of Lex is no different. He has bested his peers, his family and even Supergirl. We’d be rooting for him if he wasn’t… well, a villain. He’s successfully been a thorn in Supergirl’s side for multiple seasons, and Lex was even able to wrangle a second chance at life and success post-“Crisis on Infinite Earths.” It’s no wonder that the showrunners have been reluctant to retire the character. While we can hope that Supergirl gets to battle and defeat Lex at least once more before her swansong, perhaps there’ll still be an opportunity for Lex to return on another CWVerse show (hint: we mean Superman & Lois).

Supergirl returns for its final season on August 24 on the CW.

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