Loose Cannon (character)

Loose Cannon is a fictional superhero published by DC Comics. He first appeared in "Action Comics Annual" #5 (1993) during the Bloodlines crossover event, and was created by Jeph Loeb and Lee Moder.
Fictional character biography.
Eddie Walker used to serve with the Metropolis Special Crime Unit, until an accident crippled him. Walker was savagely attacked and bitten by the Bloodlines Parasite named Glonth. As was the case with very few of the parasite's victims, the attack triggered his metagene, granting him superhuman abilities. Eddie would soon confront one of the four Superman doubles that arose after Superman perished in the fight with Doomsday. Due to his alien connection, he is drawn to the swamps outside Metropolis where the Bloodlines aliens are hiding. He meets with other New Bloods heroes, such as Hitman and Geist to name a few. The new heroes rescue veteran heroes from the aliens and combine forces to destroy the threat.
Eddie originally transforms into his alter ego only at night, and grows in strength and size as he got angrier. He changes color from blue to purple, to red, and finally to white due to extreme rage. In his white form he is barely capable of coherent thought.
His first solo appearance was in "Showcase '94" #5 against an armed mercenary called Firepower. He also encounters the clone Superboy.
When the Secret Society of Supervillains breaks open super-prisons around the world, Oracle calls in many superheroes, including Loose Cannon. Along with Roy Harper and a small team of other heroes, Loose Cannon attempts to stop the breakout at the "Slab". His team defeats some prisoners but many more escape.
In the "Infinite Crisis" hardback special, Loose Cannon is seen attending a special mass being held for missing and or dead superheroes. Among the dozens of attendees are many of his fellow 'Bloodlines' New Bloods. In a related incident, he helps with clean up in the fictional city of Bludhaven after it is bombed. He helps defend the city of Metropolis from a mass super-villain attack.
One Year Later.
One year after "Infinite Crisis", Loose Cannon has his heart stolen by organ thieves in "JSA Classified" #19. He is seen on life support.
He is briefly seen in Metropolis, in company with several other heroes with alien influence, under the mental influence of an alien armada, in "Superman/Batman" #32 (March 2007). This situation is swiftly resolved.
The New 52.
In The New 52, an unnamed Loose Cannon first appears as a potential candidate for the Teen Titans, but he was only posing, soon attacking the team before being defeated by Wonder Girl.
Another version that is Eddie Walker appeared in the Bloodlines miniseries