Kid Devil's first appearance is Blue Devil #14.
Eddie Bloomberg was the assistant of his aunt Marla. Her aunt had her own film company where she made tons of different kinds of films. It was there that Eddie would meet the actor known as Daniel Cassidy, a young actor that had a lot of future in the movies business.
Some time later Eddie's aunt would decided to produce a new movie named "The Blue Devil". Daniel Cassidy was chosen to make the role of the hero known as Blue Devil. Everything was well until the moment that a lightning fell into the studio, merging the monstrous costume of Daniel Cassidy with his skin thanks to the power of the demon known as Nebiros. That day Daniel Cassidy died and Blue Devil was born from the ashes.
Thanks to this accident that made Daniel Cassidy become Blue Devil, Eddie desired to become Blue Devil's sidekick.
One night Eddie Bloomberg decided to sneak into Daniel Cassidy's workshop . When he was there he created for himself an armor that would be his superhero's costume. The suit granted Eddie Bloomberg powers similar to the ones of Blue Devil. That was the night that Eddie Bloomberg would become the hero known as Kid Devil, sidekick of Blue Devil.
Thanks, but no thanks
Blue Devil didn't like the fact that Eddie Bloomberg wanted to be his new sidekick. Daniel Cassidy didn't like to be a hero, so having a young kid become his sidekick would be against his desires. Eddie wouldn't accept Blue Devil declining his offer, so he decided to prove to Blue Devil what he was able to do as his sidekick.
A very high price for fame
Some time after this, Blue Devil would finally accept that he was a hero and soon after that he would join the Justice League of America.
Everything was well for Blue Devil until he started to remember how much he loved his life as an actor of Hollywood before he became a hero.
This made Blue Devil to make a deal with the lord of hell known as Neron. Neron decided to grant Blue Devil wish, however he would first need to do a favor to Neron. Blue Devil was supposed to destroy an electrical station that was in the desert before he was able to receive Neron's part of the deal.
Daniel did destroy the electrical station, however it also came with a high price. His friend and producer Marla Bloomberg's life. Apparently Neron decided to make destroying the power station part of the deal because he knew that Marla Bloomberg would be choosing a location for her new movie around there. After the explosion of the electrical station, Maria Bloomberg's helicopter crashed causing her imminent death.
This was something that was hard for Blue Devil to accept, in part because of his close relationship with Marla Bloomberg and in other part because he took the only family that Eddie Bloomberg had left just to obtain his former glory. He decided to guard the secret and never tell Eddie his part in the ordeal.
After his aunt`s death, Eddie Bloomberg would decide to follow his aunt's steps and try his hand in movies. However, things didn't go well and he was fired from job after job.
In between his jobs, he had some adventures as Kid Devil. Sometimes on his own, sometimes along Blue Devil, and one time as an ally of the team known as Young Justice. After this adventure Kid Devil considered to ask for membership on the team, However the team disbanded just after that because the deaths of both Donna Troy and Lilith Clay in Graduation Day.
After the events of Infinite Crisis, the DC universe skipped one year of continuity. During the missing year Eddie Bloomberg as Kid Devil was along the dozens of young heroes that went to the membership drive held by Beast Boy to join the Teen Titans.
However like almost everything in Eddie Bloomberg's life, things didn't go well and he wasn't accepted in the teen titans.
It was after this that Eddie would go to Lex Luthor's Everyman Project to try to gain new powers and become a more respected hero. However he also wasn't accepted there because he couldn't make the test. The doctors said to Eddie that the reason they weren't able to do the program on him was because of "psychological problems."
The Devil Inside
After being rejected by both the Teen Titans and Lex Luthor's Everyman Project, Eddie decided to find another way to get powers. Eddie managed to obtain a magical candle, which he was told would help him get what he wanted. Because he knew magic was not something he should just jump into, Eddie turned to his friend and magic-using superhero Zachary Zatara.
The candle took the two of them to Neron's realm where they met Neron himself. Just like Blue Devil before him, Eddie Bloomberg made a deal with Neron to gain something he desired.
The deal was Neron would give Eddie Bloomberg powers similar to the ones of Blue Devil, However if the trust that Kid Devil had for Blue Devil was ever broken he would become Neron's servant for all eternity. Eddie accepted since he trusted Blue Devil with his life and thought that his trust with him could never be broken.
Neron granted Eddie's wish and transformed him into a being that looked exactly like a devil and gave him powers similar to the ones of his former mentor.
Eddie revealed to Zatara that it had always been his dream and vision to become this version of Kid Devil instead of using a battle suit.
Just after this transformation Neron decided to reveal to Eddie the deal that he had done with Blue Devil years ago to let him gain his former glory and how it had ended with Marla Bloomberg's death.
After getting his powers, Kid Devil joined as a member of the Teen Titans along with Deathstroke's just reformed daughter, Rose Wilson ( Ravager). The two of them quickly became close friends leading to Kid Devil having a crush with Ravager. While he was in the Teen Titans, Eddie regularly pretended to have phone calls from Blue Devil since a requirement for being in the Teen Titans was to have an adult supervisor in case that anything happened.
After Robin returned to the role of the leader of the Teen Titans, the team confronted the newest incarnation of Brother Blood. After a hard battle Kid Devil was heavily injured and was taken to the headquarters of the new Doom Patrol through Beast Boy's contact with them.
The chief examined and cured Kid Devil's body and discovered that Eddie wasn't really a devil but a metahuman whose powers hadn't been activated until recently by a mysterious force (the force was Neron's power).
Some time after this Kid Devil would decide to confront Blue Devil and ask him the truth about what Neron had told him about his aunt's death. Blue Devil said slowly to him that all of that was true and that it was all an accident, because he also wanted to use that glory to help Eddie's aunt.
Kid Devil couldn't tolerate what his former mentor had told him, so completely angered with Blue Devil he said that he would never trust him again. This was the turning point in Kid Devil's life, because now that his trust in Blue Devil is broken thanks to his deal with Neron he'll become his servant as soon as he becomes 20 years old.
After proving himself a stable and loyal member to the team, Eddie becomes constantly dumped on with things. The Teen Titans are falling apart, and he has no powers. Ravager and Robin leave following the battle with Clock King, which took a vicious toll on the entire team. When Wonder Girl (who is technically the acting leader after Robin's departure from the team) finds out about Eddie's deal with Neron, she enlists Kid Eternity to help Eddie figure out his situation. Kid Eternity takes Eddie into Hell, where they review Eddie's contract and discover that his signature has vanished! It is then that Blaze, the new ruler of Hell, explains that since his powers where taken from him and not returned (I'm guessing because Neron died in the battle for hell), the contract was breached and nullified. Then, Blaze offered to to rectify this with a new contract. Eddie's powers would be returned to him irrevocably in return for his eternal servitude on Eddie's 20th birthday. Before Eddie could sign, Kid Eternity used his abilities to summon Eddie's Aunt. She talked Eddie down, explaining that she had also formed some sort of deal with Neron, and that Blue Devil was tricked just like Eddie was.
Eddie returned to the Titans, powerless, but still a member. Wonder Girl assured him that everything would be fine although Eddie severely doubted that he would still be a contributing member of the team but proved a few times to be useful. He even once donned his old costume before he got his powers and helped defeat the hacked Titans Tower with his old weapon. Later on after the Deathtrap arc (where nothing really interesting happens to him) he and Rose meet up again. She talks to him and tries to convince him to leave with her stating that he could end up like Marvin. It seems as if Eddie would accept this offer but turned it down deciding to stay with the Teen Titans instead. Later on, while Wonder Girl and the team are fighting off the Fearsome Five, Eddie realizes that there is an eminent explosion to come, possibly ending his life. He took immediate action while the other Titans were busy, contacting the FBI. His call was intercepted by Calculator who misled him. None of the FBI people around would help Eddie so in the end, he took the convict causing the explosion (a villain named Geiger had nuclear powers) and flew up into space where the ship he was in exploded, killing both him and the convict. The other Titans were unable to save him in time.
Eddie Bloomberg is the god-son of Daniel Cassidy who is out with friends, one of whom takes some of the drugs distributed by Tobias Whale. As Jason, his friend, becomes to froth at the mouth, Eddie tells one of his friends to call the authorities and then carries his friend to a church where Jason explodes.
Powers & Abilities
While Kid Devil wore his super-suit, his strength was increased by a factor of ten. The suit enabled Kid Devil to leap great distances. It also increased his agility and endurance. In addition to the suit, Gopher fashioned a number of gadgets - including a bright-light burst, exploding bubbles, and night vision goggles. But his most effective weapon was his devil trident - which emitted an electroshock or flames, and contained a jet propulsion to aid Kid Devil's air travel.
Later, Eddie "transformed" into a demonic creature. Kid Devil has enhanced strength, endurance and agility. Kid Devil also breathes fire, has a prehensile tail and has collapsible bat-like wings. He has an accelerated healing factor that allows him to recover from injuries ten times faster than normal humans.