Change! Change, O form of man! Release the might from fleshy mire! Boil the blood in heart of fire! Gone! Gone! — the form of man — Rise, the Demon Etrigan!!
— Jason Blood
Created by Jack Kirby and appearing for the first time in The Demon #1 (August, 1972), Etrigan has played many smaller roles in several DC comics from The Sandman to Wonder Woman, with occasional stories and miniseries wholly to himself (such as in anthology series Wednesday Comics), and a number of ongoings, including Kirby's original series, a fifty-nine issue run, not counting annuals, during The Nineties, and John Byrne's Blood of the Demon.Etrigan is a yellow skinned and red eyed demon who was summoned by Merlin to aid Camelot against the forces of Morgaine le Fay, who later became a recurring opponent in the series. After the fall of Camelot, Merlin sent Etrigan to roam the earth in the disguise of a man. Depending on the Writer, Etrigan is either bonded to one of King Arthur's noblemen or the human Jason Blood was merely created by Merlin's spell. In the present, Jason Blood is well versed in the skill of magic and has helped other superheroes in several occasions. Etrigan's habit of speaking in verses is a later addition, introduced by Len Wein in DC Comics Presents #66, but really established and explained by Alan Moore. This also makes him fall under almost every rhyme Trope there is.Etrigan's powers include superhuman strength, speed, durability, regenerative powers, hellfire projection, teleportation, and a high knowledge of maleficium. Jason Blood on the other hand is precognitive, as well as a capable sorcerer himself.Etrigan has also appeared in various animated adaptations of DC comics, being played by Billy Zane in Batman: The Animated Series, Michael T. Weiss in Justice League, Dee Bradley Baker in Batman: The Brave and the Bold and Justice League: The Flashpoint Paradox, and Christopher S. Field in DC Universe Online.His latest ongoing, Demon Knights, sees Etrigan leading a Ragtag Bunch of Misfits in Dark Age Europe.
Badass: Etrigan was rampaging through Hell when he was still a child and even higher level demons are afraid of the havoc and destruction he commits. He frequently goes hand to hand with people such as Lobo and Superman, Wonder Woman and other DC heavy hitters.
Battle Strip: Averted. Since the transformation from Jason to Etrigan is magical in nature, Jason's clothes aren't destroyed during the change and Etrigan appears fully clothed.
Blessed with Suck: Jason is thousands of years old, has witnessed the birth and fall of nations, traveled the world, and become a future seeing sorcerer. Oh...and he is forever bonded with a destructive, demon from Hell and they both don't get along. At all.
Blood Knight: Etrigan, even when he is acting as a hero on the side of the good guys, never tries to make it a secret that he enjoys fighting and general destruction.
Breath Weapon: Etrigan can breath hellfire from his mouth, though he can also project it from his hands.
Often, especially in adaptations, only the two last lines are used. To change back, he recites "Gone, gone, O Etrigan! Resume once more the form of man!"
Other versions of the poem have been seen to work. Spoofed at least once by Blood himself, while in a particularly snarky mood:
Gone, oh little man so tame, Arise the demon... Whatsisname?
Child Mage: Klarion the Witch-Boy is an absurdly powerful little brat who, in his first appearance: cures a deadly poison, conjures up a feast, banishes a monster with a fork, and summons the Demon to his aid while tied up and suspended from the ceiling.
Cigar Chomper: Henry won't let go of a cigar even in a dead faint.
Magic Knight: Jason was a literal knight of Camelot. And he has picked up a lot of useful sorcery over his few thousand years of life. However he is more of a "sit in a mystic circle and chanting" kind of magician.
Planet of Hats: Klarion is from Witch-World, a dimension where everyone has at least some skill in wizardry. However, being a child, adults were constantly telling him what he could and couldn't do with his powers and what kinds of sorcery he could and couldn't practice. Coming to our dimension where he was free to do whatever he wanted solved that problem for him.
Really Gets Around: Belial, Etrigan's father has three children, by three different mothers. Though considering he is a very high ranked demon, it's understandable he'd have multiple wives.
The Trickster: Frequently, Etrigan's own motivation is his own amusement... such as when he intentionally triggered a war between Heaven, Hell, and Purgatory over the vessel of God's divine rage, just to get more serious (and dull) demons abused when the heroes inevitably won.