The intergalactic heroes of DC's cosmos, the Green Lanterns, are as defined by their adventures on Earth as they are by their patrolling of space. Names like John Stewart, Hal Jordan, and Kyle Rayner ring loud in the halls of celebrated heroes as they keep Sector 2814 at peace.

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While the Green Lanterns and their allies fight earthbound as well as cosmic crime, some villains are worse than others. Between evil Lantern corps, bloodthirsty supervillains, and galactic evil scientists, the Emerald Knights work hard to ensure no evil escapes their sight.

10 Major Force Is The Origin Of "Fridging"

Major Force looks forward in a mock-heroic pose

Compared to galactic-scale villains like Sinestro and Atrocitus, Major Force seems like small potatoes. Originally a Captain Atom foe, Clifford Zmeck was a dark mirror of the hero, boasting antimatter powers and a desire to do government dirty work. However, it was as Kyle Rayner's enemy that Force became most infamous.

In Green Lantern (Vol. 3) #54 — by Ron Marz, Steve Carr, Derec Aucoin, Darryl Banks, Romeo Tanghal, Steve Mattsson, and Albert DeGuzman — Force killed Rayner's then-girlfriend, Alex DeWitt, and stuck her corpse inside a refrigerator. This led writer Gail Simone to coin the phrase "fridging," a term that refers to the fictional trope of a male main character's female love interest being murdered to further his story.

9 Arkillo Trains Others To Know Fear

Arkillo bursts forward with yellow constructs of teeth and hands

Contrary to what the name makes some think, Sinestro isn't the only member of the Sinestro Corps. One of its most formidable members is Arkillo, a blue-skinned alien who serves as the Corps' Kilowog equivalent, training new Corps recruits and eating those who didn't meet his standards.

More than any other, Arkillo is dedicated to the Sinestro Corps, at one time being its sole surviving member. Handpicked personally by Sinestro for his ability to instill fear, Arkillo stayed with the group even after its new leader, Mongul, ripped Arkillo's tongue out to wear as a necklace.

8 The Star Sapphires Argue That Love Is All You Need

Star Sapphire Carol Ferris looks off into the distance

Carol Ferris debuted as the vice president of Ferris Air, the company where Hal Jordan tested aircraft. After Carol and Hal began a relationship, the Zamarons selected Ferris to serve as their Star Sapphire, an incarnation of their queen imbued with Green Lantern-like powers of energy projection.

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The Star Sapphires were later retconned to be another corps of the Emotional Spectrum, representing love. The primarily female corps often fought on the side of good, but the Star Sapphire's extreme interpretations of love led to repeated conflict.

7 The Manhunters Are Cybernetic Space Police

A pair of Manhunters fly through space towards the reader

Invented by the Guardians of the Universe as a precursor to the Green Lantern Corps, the Manhunters' internal logic was corrupted first to focus on hunting people, then to taking revenge on the Guardians and Lanterns for abandoning them. Boasting the ability to drain Green Lantern batteries and harness the energy for themselves, the robot Manhunters have continually sought to undermine the Guardians.

Over the course of their history, the Manhunters have formed Manhunter cells across alien worlds, joined the Sinestro Corps, and even battled the Olympian gods. An intergalactic hivemind with little emotion, the Manhunters pose a serious threat to even the most seasoned Lantern.

6 Atrocitus Invented A Lantern Corps of Hate

Atrocitus ringed by the red blood fire of rage

Geoff Johns's introduction of the Lantern Corps Spectrum blew the door off of the Green Lantern mythos, introducing a new world of color to the galactic side of the DC Universe. Of the new groups, the most fearsome was undoubtedly the Red Lantern Corps, led by the murderous Atrocitus.

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After the Manhunters killed everyone he knew, Atrocitus became a terrorist bent on killing the Guardians of the Universe. Atrocitus later formed the Red Lantern Corps, a group similar to the Greens. Although occasionally a force for his own brand of vengeful justice, Atrocitus was never afraid to spill blood.

5 Krona Is A Multiversal Peeping Tom

Krona arguing in DC Comics

An Oan like the Guardians of the Universe, Krona was the initial reason for the group's formation. Krona was obsessed with viewing the forbidden birth of the universe, an act that caused the other Guardians to transform him into a being of pure energy who wandered the cosmos until his eventual restoration by Nekron.

Krona has continually come into conflict with the Guardians, forever viewing them as his enemies. However, Krona's biggest claim to villainous fame is in the pages of Kurt Busiek and George Perez's JLA/Avengers, which depict his universe-peeping machinations bringing the DC and Marvel Universes together in an epic clash.

4 Nekron Sought to End All Life

DC Comics' Nekron looms large against the cosmos

A demon who controls a realm of DC's hell dimensions, Nekron is DC's embodiment of Death. Nekron has power over the souls of all who have ever died, using it for godly abilities of strength, durability, and energy projection. Not content with his own realm, he has often sought control over the rest of the DC Universe.

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Nekron's biggest power play was the DC event Blackest Night, where he co-created the Black Lantern Corps with the Black Hand. Using the bodies of formerly dead heroes like Superman and Wonder Woman, Nekron sought to eliminate all life in the universe.

3 Black Hand Delights in Death

Black Hand looks off to the right while in the rain in DC Comics.

While Nekron was the metaphysical entity behind Blackest Night, the Black Hand was the sinister agent who made it all possible. A former supervillain who sought the power of a Green Lantern ring, William Hand was convinced by Nekron and Scar to return all the living to the dead.

Black Hand became the personification of death, delighting in the emotional and physical sufferings of various heroes, villains, and civilians. Following the event, DC continually portrayed Black Hand as a violent murderer, seeking to kill and reanimate his victims in a gruesome mockery of life.

2 Parallax Nearly Destroyed Green Lantern

Hal Jordan as Parallax bursts out of a Green Lantern logo in DC Comics.

As Nekron is the universal embodiment of death, Parallax is the embodiment of terror. Deriving his powers from the yellow light of fear, Parallax is usually presented as a serpentine creature who acts as a parasite in a host mind. The most notable example of a Parallax infection was that of Hal Jordan.

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First appearing in the 90s when DC sought to give their heroes a new edge, the comics presented Parallax as Jordan's villainous persona. Green Lantern massacred the rest of the Corps and destroyed his home of Coast City. The decision frustrated many readers and made Hal Jordan difficult to portray until Parallax's true parasitic nature was revealed.

1 Sinestro Reveals How Power Can Corrupt

Sinestto Flying at the reader against a yellow background, power ring aglow

First the greatest of the Green Lanterns and then their greatest enemy, Sinestro remains one of the DC Universe's most enduring antagonists. After becoming a Lantern to further instill order over the galaxy, Thaal Sinestro put his homeworld of Korugar under his own totalitarian control.

It was only when Sinestro's protégé Hal Jordan exposed his work to the Guardians that Sinestro was removed from the Corps.

Since then, Sinestro menaced the DC Universe as a Legionnaire of Doom and the founder of the Sinestro Corps, harnessing the yellow energy of fear. Although Sinestro occasionally commits noble acts, his hatred, anger, and desire for power ultimately define him.

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