Judge Kraken

Judge Kraken was a character in 2000 AD comic strip Judge Dredd and was a major character despite only appearing in "Tale of the Dead Man" and was even the main protagonist in the first half of "Necropolis" due to Judge Dredd going on the Long Walk.

Origins
Judge Kraken is a clone created using the DNA of Chief Judge Eustace Fargo and is basically a twin brother of Judge Joe Dredd despite being many years younger.

He started of as being part of the Judda, a rogue army of Judge clones created by Morton Judd to take over Mega-City One but after the Judda base is destroyed and Morton Judd and most of his clones were killed, Kraken was taken prisoner and the only one to be spared from execution, he instead went through a lengthy deprogramming to eradicate his loyalty to Morton Judd and was then trained to be a Judge. Secretly Chief Judge Silver was using him as a replacement due to Dredd having doubts about the Justice Department.

Kraken's assessment
Judge Dredd was chosen to supervise Rookie Judge Kraken to confirm is he's suitable to graduate to become a full street Judge. Kraken performed exemplary, his skills and judgement being more superior than Dredd himself but Dredd has noticed traces of loyalty to the Judda so he therefore failed him. Unfortunately Kraken's original death sentence for being a member of the Judda was re-imposed.

Judge Dredd.2
After Kraken's assessment, Dredd decided to resign from the Justice Department and took the Long Walk into the Cursed Earth, a post apocalyptic desert wasteland. Chief Judge Silver, however, secretly ordered Kraken be spared from execution and, ignoring Dredd's assessment, made Kraken a full street Judge. He used Kraken as Dredd's replacement to make sure the city doesn't know about Dredd's resignation.

Enslavement
Kraken was then "visited" by the Sisters of Death, a pair of evil spiritual beings and they began to manipulate and played with his doubts and confusions by making him hallucinate Morton Judd and the Judda. They managed to easily take control of his mind and used him to get Psi Judge Kit Agee, whose body the Sisters are going to use to build a doorway between Mega-City One and Deadworld. They managed to rescue the Dark Judges from their imprisonment in the void, enslaved by turning him into a fifth "Dark Judge", and they immediately created 'Necropolis', completely enslaving Mega-City One and completely control the Judges and proceeded to start the extermination of the population with Kraken being forced to take part in the slaughter. Within a few months 60 million citizens were slaughtered.

Facing Death with Dignity
Fortunately Dredd, with Judge Anderson and former Chief Judge McGruder and handful of Cadet Judges, manage to defeat the Sisters by killing Agee, sending the Sisters back to Deadworld and Judges Fire, Fear and Mortis were captured, with Death escaping. Kraken was finally free of the Sisters and the Dark Judge's influence but Dredd stated that while he doesn't hold any blame on Kraken, he can't allow Kraken to live, which Kraken thanked Dredd for and allowed himself to be killed due to the guilt of his part in the slaughter.