|First appearance||Justice League Europe #15 June (1990)|
|Created by||Keith Giffen writer
J.M. DeMatteis writer
Bart Sears artist
The original Extremists were a team of supervillains from the other-dimensional world of Angor, first introduced in the DC Comics series Justice League Europe. Like the Champions of Angor they were based on Marvel Comics characters.
The Extremists were destroyed, along with the other inhabitants of Angor, in a nuclear holocaust they themselves had engineered. However, prior to this, a theme park had created robot duplicates as part of a ride. The duplicates proved to be too accurate, and went on a rampage, eventually tracking the remaining Champions of Angor to Earth, where they attempted to reprise the final act of the originals. They were defeated by the League and Heroes, with help from Mitch Wacky, the founder of the theme park. Dreamslayer proved not to be a robot; he had survived the nuclear event owing to not being human. While the others were switched off, he was defeated by the Silver Sorceress.
The Extremist robots were taken to "Madame Clouseau's" (a parody of Madame Tussauds) in London. They were subsequently restored by Dreamslayer when he possessed the body of Maxwell Lord during the Breakdowns storyline. Dying from an arrow inflicted by a mind-controlled slave, the Sorceress still manages to defeat Dreamslayer. Since they were being powered by Dreamslayer's magic, the robots stopped at the same time.
New Extremists 
Trapped in the Astral Plane, Dreamslayer was contacted by the Overmaster, who helped him set up a villain team called the New Extremists. This was part of the lead-up to the Judgment Day storyline. After he had achieved his purpose, Overmaster sent Dreamslayer back to his astral prison. The New Extremists joined Overmaster's Cadre, and are assumed to still be at large.
Extremists return 
The Extremist robots later appeared in Peter David's Supergirl, activated by Supergirl's foe Twilight. Power Girl assisted in stopping the murderous rampage. Although how the creatures were rebuilt was not revealed.
The robots also appeared in the JLA/Avengers miniseries.
Earth-8 Extremists in Countdown 
In the aftermath of Infinite Crisis, another universe's Extremists are a group of villains from Earth-8 who have refused to comply with a government ordinance mandating that all metahumans need to register with the government. In Countdown #29, they are encountered by Donna Troy, Jason Todd, "Bob" the Monitor, and Kyle Rayner during the heroes' search for Ray Palmer. They capture the group, but are interrupted by the arrival of Bob's overzealous brother, and at the same time, Monarch (Nathaniel Adam) and Forerunner. In the confusion, Jason and the others move out of sight, and the Extremists are offered a place in Monarch's army. Lord Havok refuses, attacking Monarch, and Jason kills Barracuda.
The Extremists had their own six-part miniseries, starting in October 2007. In #1, the origin of the new Extremists is revealed; They were superbeings refusing to submit to the Metahuman Act, a government mandate requiring all Metahumans to submit to government control. (An obvious parody of Marvel's Civil War miniseries.) They battle against the Meta Militia, a group led by Tin Man (a parody of Iron Man). They currently reside in a captured country called Slovekia. After Havok's refusal, Monarch's forces attack Tracer and begins destroying places of great significance to the Extremists, making it look like they destroyed them.
In Countdown To Final Crisis #13, Superman-Prime rips open Monarch's armor, causing an explosion that eradicates all of Earth-51. Lord Havok uses a tiny portion of Monarch's power, stolen during their first encounter, to teleport himself and the Extremists to a base hidden in Earth-8's moon.
- Lord Havok - The team's leader. An arrogant villain concealed by cybernetic armor. Based on Doctor Doom. The second incarnation of Lord Havok was actually a robot animated by the mind of Maxwell Lord.
- Dreamslayer - A powerful sorcerer, and possibly a demonic entity, with an energy cloud covering his head. He called himself "Lord of the Dimension of Terrors". Based on Dormammu. In the new Extremists series, he is actually a she and has her own religion, complete with worshippers.
- Gorgon - An overweight man with tentacles growing from his head with two cybernetic claws for hands. Based on Doctor Octopus. In the new Extremists series, he is able to transform from human form to his Extremist form, which is much shorter than the original version.
- Tracer - A feral man, with blades attached to his arms. Based on Sabretooth, though the Earth-8 version has strong similarities to Wolverine
- Doctor Diehard - A master of magnetic force, who wears a red cape and a helmet that leaves his face uncovered. Based on Magneto. The Earth-8 version also has his own school for his "Zen Men," in reference to Professor X.
- Carny - Debuted as a robot in the "Extremist Vector" storyline in JLE #15-18. Reappeared as a human in "Lord Havok and the Extremists" #1, where he was killed by Lord Havok for refusing to serve him. He is based on Marvel's villain Arcade.
- Barracuda - An aquatic villain reminiscent of Marvel's Tiger Shark.
New Extremists 
- Brute - An unnintelligent powerhouse.
- Cloudburst - A man with weather-controlling powers.
- Death Angel - A woman with claws, possibly poisoned.
- Gunshot - A taciturn weapon-user.
- Meanstreak - A vicious woman who could fire energy-bolts. Reappears in Salvation Run.
Earth-8 Extremists 
- Versions of Lord Havok, Dreamslayer, Dr. Diehard, Gorgon, Tracer, and Carny exist on this earth, with the addition of a new character, Barracuda II, a fish-like being based on Attuma.
Other media 
- The original Extremists (minus Doctor Diehard) appeared in the Justice League Unlimited episode "Shadow of the Hawk". They were not shown as being terribly effective against the Justice League.
- Jimenez, Phil (2008), "Extremists, The", in Dougall, Alastair, The DC Comics Encyclopedia, New York: Dorling Kindersley, p. 117, ISBN 0-7566-4119-5, OCLC 213309017
- Beatty, Scott (2008), "Extreme Justice", in Dougall, Alastair, The DC Comics Encyclopedia, New York: Dorling Kindersley, p. 117, ISBN 0-7566-4119-5, OCLC 213309017
- The DC Comics Encyclopedia, Dorling Kindersley Limited, 2004, p. 199, ISBN 0-7566-0592-X