PSI: AKA Gail Marsh. Empowered with telekinetic and telepathic powers via the Meta-Human gene, Gail abandoned any semblance of being an upstanding citizen when she discovered she could bring anyone to their knees just by thinking of their fears. After a series of bank robbers, Psi appeared on the D.E.O.'s radar as a major threat. After her first encounter with Psi, Supergirl turns to J'onn J'onzz to help control her. J'onn is quickly dispatched by Psi as she is a much more powerful telepath. Only Supergirl's inner strength will be a match for this Meta-Human villain.

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BLOODSPORT: AKA Robert Dubois, is a mercenary for hire. He was hired by Morgan Edge, a National City industrial developer, to disrupt Girl of Steel day. By creating an act of domestic terrorism, Bloodsport was looking to level a large waterfront area of National City. Morgan Edge was hoping to buy up the property afterwards for pennies on the dollar and create a new upper-class only development.

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LAR GAND: King of Daxam and father to Mon-El, Lar Gand's motives are unclear. The character's name has a very rich history in comic book lore. Lar Gand was actually the real name of Mon-El. Lar took up the mantle of Mon-El after his time with Superman. As a hommage to the Man of Steel, he took his Kryptonian last name. Lar Gand, however, may not have heroic ambitions in the Supergirl universe has his wife is Queen of Daxam Rhea, commander of the palace ship of the royal family.

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RHEA: Queen of Daxam, the sister planet to Krypton, is the mother of Mon-El. After Krypton's destruction, the King and Queen of Daxam set out to find their son, Mon-El, who was sent in a Kryptonian pod to Earth. They didn't know which planet Mon-El escaped to but through luck and the events on Slaver's moon, the pair was able locate Mon-El. Their exact motives are unknown but as Queen, Rhea commands a vast Daxam battle ship as well as many soldiers with powers lesser but similar to Kryptonians under a yellow sun.

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MUSIC MEISTER: This version of the character is an extra-dimensional being with the ability to hypnotize people through his eyes, sending them into a dream based on their personal desires. He also can absorb the powers of those he hypnotizes while they are trapped in the dream world, and can materialize anywhere. This version of the Music Meister isn't really a villain. He is someone who tries to help others in his own ways. He states that he believes in the good guys. In the end, was he a guardian angel or just a powerful nuisance?

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MXYZPTLK: A fifth dimensional imp with powers that are beyond any in the Supergirl CW TV Universe! With a simple snap of his fingers, Mxyzptlk or Mxy can create reality as he sees fit. Cracking the Earth in two, rebirthing Krypton from its ashes, even ending reality as a whole are but a simple snap away for this villain. That said, villain is potentially a harsh term for Mxy. He is misguided and doesn't understand freewill and love but his intentions are to win Kara Zor-El's heart. His power alone is what makes him so dangerous. Luckily, 5th dimensional creatures only appear in our existence with a series of rules that they layout. This includes keeping a beings' freewill intact, and most importantly if they say their name (or write it) backwards, they are forced to return to their dimension.

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ARMEK: One of the most deadly and dangerous White Martians to ever exist. He was the companion to M'Gann M'orzz when she was a White Martian on Mars. M'Gann removed herself from the Martian conflict and severed ties with Armek in doing so. Armek, however, came to Earth to get M'Gann back and take her to Mars for trial for the perceived war crimes she committed.

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DOMINATORS: The Dominators exist in both Earth 38 and Earth 1 universes. While only historical records from Krypton can explain the Dominators in Earth 38's universe, the Dominators have made a big appearance on Earth 1. The Flash and Vibe traveled to Supergirl's world to ask for her help against this terrifying race. The Dominators fear the rise of the meta-humans on Earth 1 and when the Flash causes the alternate time-line Flashpoint, the Dominators decide that Earth can no-longer be left alone for the sake of the universe. The Dominators are technologically advanced, stand taller than humans and are very strong. They have extremely sharp teeth and are adept at mind control technology.

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CYBORG SUPERMAN: Hank Henshaw, or the real Hank Henshaw, was the head of the D.E.O. before J'onn J'onzz took his identity. He was thought killed after Jeremiah Danvers threw him off a cliff saving the life of J'onn. Laying on the ground near death, Cadmus found Hank and brought him back using alien technologies. He is now filled with anger and rage against aliens, especially J'onn, Supergirl and Superman. He has super strength, speed and perhaps other powers. In his hate, he has renamed himself, The Cyborg Superman.

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PARASITE: Rudy Jones is a scientist who is infected by an alien parasite during an autopsy of a frozen wolf that was oddly emanating heat signatures as if it were alive. Eventually, Jones is transformed into a larger and monstrous alien/human hybrid called "Parasite" after sucking the powers of both Supergirl and Martian Manhunter, leaving the latter in critical condition, with the Parasite also targeting anti-global warming politicians.

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LILLIAN LUTHOR: Lillian is shown to be very much like her son, Lex; cold, self-righteous, unstable and delusional in her views. Blaming Superman for her son's imprisonment, while completely ignoring the horrific actions Lex performed, she has come to develop radically-driven disdain for aliens of all kinds. Viewing them as a poison to Earth, beings who are subtly taking control of the planet by making humans worship them, she is determined to purge Earth of these otherworldly-forms. To that end, she takes over Project Cadmus, a secret lab that studies aliens, and severed its relationship with the government.

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ROULETTE: Roulette, also known as Veronica Sinclair, is a wealthy socialite who secretly made money holding alien fight clubs for rich people to bet on but at the same time forced the aliens to fight for their freedom. Her illegal activities drew the attention of M'gann M'orzz, who became one of her best fighters. Her look is rather distinct as she is known for wearing a red dress and has a full body dragon tattoo.

For more on Roulette, check our our partners at ArrowverseWiki.

METALLO: John Corben was initially hired by the then-arrested Lex Luthor to assassinate his sister Lena Luthor to prevent her from rebranding Luthor Corp. His first two attempts to kill Lena fail due to the intervention of Supergirl and Superman and his third attempt is foiled by Alex Danvers and Lena who shoots Corben when he tries to take Alex hostage. While being sent to the hospital, he is intercepted by Project Cadmus who perform an experiment to convert him into Metallo (a Kryptonite powered cyborg). Then they unleash him on Supergirl and Superman.

METALLO 2: Cadmus isn't satisfied with just one Metallo. The very same process Dr. Gilcrist developed to make Metallo is used against him to become Metallo 2.

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SILVER BANSHEE: It is revealed that Siobhan Smythe's family was cursed generations ago by a banshee. It causes the women in her family to be possessed by a banshee spirit when they are particularly angered; they develop a sonic scream that they can potentially send anywhere in the world. However, unless they kill the object of their rage, the banshee spirit will take their souls. Silver Banshee may be one of the most powerful villains when teamed with Livewire. The pair certainly are too much for just Supergirl, but not Supergirl and her friend ... The Flash!

RED-K SUPERGIRL: Possibly the most dangerous villain on the whole show is also our hero in black. Red-K Supergirl isn't necessarily a villain but is the result when Kara is exposed to synthesized Kryptonite (red) resulting her Kara turning evil. The only way to stop Kara is with someone else as powerful as her and getting the synthetic Kryptonite out of her system. The first time Kara was exposed, J'onn J'onzz had to reveal his true identity making him an enemy of the state!

INDIGO: Indigo, previously named Brainiac-8 is a Coluan. Indigo initially appears as a blonde human on video monitors, eventually crossing paths with Supergirl. Indigo hacks a secret military base as well as teaming up with Supergirl's uncle and nemesis Non. She reveals to Supergirl that she was the reason Fort Rozz and Supergirl escaped the Phantom Zone. Her plan was to destroy National City with a nuclear weapon, but was stopped by Winn Schott, Jr. when he downloads a virus into her. Later, Non reanimates her to kill all of the people in National City using Myriad. Indigo is stopped again, this time by the Martian Manhunter when he rips her body in half.

NON: Non was imprisoned with his wife in the Phantom Zone when Krypton was destroyed, and he, his wife (Astra), and an army of other aliens managed to escape the Phantom Zone when Kara Zor-El's pod first crashes into Earth. Astra leads them with the intention of saving Earth from humanity, but for years they are hunted by the American government's DEO, while Kara Zor-El, known as Kara Danvers on Earth, grows up. Once Kara takes on the mantle of Supergirl, she aids her adoptive sister Alex Danvers, DEO agent, in hunting the Phantom Zone escapees. Non pressures Astra to proceed with her plan to "save" the Earth, despite her knowing that she must kill her niece Kara to succeed. After Astra is killed at the hands of Alex Danvers, Non takes command of the remaining Kryptonians and sets out to do her bidding.

BIZZARO: Was a pet project of Maxwell Lord, Genetically modified to look like and have the same powers as Supergirl, she picks up a vehicle from a bridge and tosses it, while the real Supergirl and her foster sister Alex Danvers watch on their TV set. Bizarro attacks Kara on her date with Adam Foster. Her skin cracks and turns gray-white when hit by kryptonite fired by Alex Danvers. She later kidnaps James Olson, but is finally stopped by Supergirl and Alex with blue kryptonite bullets. Supergirl takes the incapacitated Bizarro back to the DEO where she is returned to a coma state until they can find a way to help her. This version isn't a clone, but instead was created by genetically altering a permanently comatose human female that closely resembles Supergirl and infusing her with Supergirl's DNA. A total of seven girls were used by Lord for the experiment, the rest presumably discarded as failures.

WHITE MARTIAN: As a race, there are nearly no other aliens more terrifiying than the White Martians. Powered with super-speed, strength, telepathy, and shape-shifting, the White Martians are responsible for the mass genocide of the Green Martians. A unnamed White Martian has attemped to kill J'onn J'onzz, the last surviving Green Martian. He was captured by Supergirl and The Martian Manhunter and is imprisoned in the D.E.O. After imprisonment, it tells Kara that there are millions more ready to attack. Kara tells the White Martian that she'll be ready for them, too.

TOYMAN: More than a decade ago, Winslow Schott tried to blow up his boss Chester Dunholz with a bomb disguised as a gift for supposedly stealing his projects. The bomb spared Dunholz, but killed six employees. At the time of the bombing, his son Winn Schott Jr. was 11 years old and had never forgiven him for giving in to his rage. After Schott escapes from prison, he attempts to kill Dunholz again, even going as far as to cajole Winn into joining the plot lest he blow up an entire convention center, before ultimately being apprehended by Supergirl.

JEMM: An alien found on Earth with powers that include super strength, telepathy, psychokinetic blasts and invulnerability sufficient to shrug off bullets. Jemm is normally held by the DEO in a special cell. He is defeated by the Martian Manhunter.

RED TORNADO: The Red Tornado is a combat android designed by Dr. T. O. Morrow for use in the United States Army. The division responsible for commissioning the android is headed by Lucy and Lois Lane's father, Sam Lane. Red Tornado was created to combat threats as powerful as Superman and Supergirl. It is even designed to challenge Supergirl and her cousin should they go rogue.

LIVEWIRE: Leslie is a confident, abrasive and funny shock-jock who works for CatCo and becomes as dangerous and shocking as her words following an accident in which Supergirl rescues her from a potential helicopter crash during a lightning storm. The rescue backfires when Supergirl gets struck by lightning while pulling Leslie out of the helicopter—electrocuting them both and giving Leslie electrical powers.

REACTRON: Former reactor engineer Ben Krull becomes Reactron when he is exposed to radiation after a terrorist attack. The attack is stopped by Superman and Ben survived the radiation, but his wife Alyssa did not. Ben blames Superman for his wife's death and swore vengeance on him. He then built an advanced bio-medical exo-suit capable of firing highly concentrated bursts of energy while also giving him super strength and the ability to fly.

VARTOX: An alien convict, who has been hiding on Earth for the past twelve years. After Supergirl’s emergence on Earth, Vartox seeks her out to ascertain her identity and do battle with her. Vartox is played by Owain Yeoman.

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ASTRA: When she was a child, Astra and her twin sister Alura took pleasure in confusing their parents. Later in life, Astra taught her niece, Kara, the names of the stars on various nights. Astra was later sentenced to imprisonment in Fort Rozz by Alura. After Fort Rozz crashed to Earth, Astra traveled with it as a prisoner. It crashed in a field, releasing all of the prisoners. From there, Astra led various of them through her subordinate, The Commander, in the hopes of seeking revenge on her sister, Alura. Astra is also played by Laura Benanti

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