Tharok is a villain from the Justice League comics.
He was a criminal on his native planet of Zadron. During one of his crime activities, he tried to steal a nuclear device that detonated when he was caught by an officer of the Science Police. Unfortunately for Tharok, that officer shot a blast which caused the detonation and it destroyed the complete left side of his body. Miraculously, Tharok remained alive and he was rushed to the nearest medical center. The doctors and scientists there quickly replaced his missing left side with a robotic component. The procedure was rushed because they feared they would lose Tharok's life. When Tharok revived, he found himself significantly smarter, thanks to his half-robotic brain. Unfortunately, the life-saving procedure also caused Tharok to look like a monster and his appearance gave him nothing but anguish.
Tharok continued in his life of crime, though significantly more successful thanks to his robotic components and new-found intelligence. However, he was eventually caught by some officers of the Science Police and was about to head to prison when Cosmic Boy of the Legion Of Super-Heroes arrived with a full pardon if he joined him in defeating a galactic menace known as the Sun-Eater. The Legion of Super-Heroes were forced to find the aid of four other super-criminals with enough power to defeat the Sun-Eater. The five criminals, with Tharok as their leader, became known as the Fatal Five although he and Emreald Empress switch roles these days.
The Fatal Five and the Legion of Super-Heroes effectively defeated the Sun-Eater. While they received their pardon for past crimes, the Fatal Five felt that their group was powerful enough to rule the galaxy. Somehow Tharok's robotic mind was able to control the powerful Validus, which cemented his leadership with his fellow criminals. They've fought against the Legion of Super-Heroes several times when they tried to gain control of the universe, and Tharok often found defeat at their hands. Besides being obsessed with ruling the galaxy, Tharok also became obsessed with making the left side of his body more human-like.
Tharok appeared in Justice League: Unlimited episode "Far From Home" as the leader of the Fatal Five. He clashed with the Emerald Empress due to her failure of capturing the Green Lantern John Stewart instead of Brainiac 5 as originally planned. Tharok fought against the Legionnaires, Supergirl and Green Arrow. He was defeated when Bouncing Boy bounced on the Persuader and slammed him onto Tharok.
Legion of Super-Heroes
Tharok appeared in the animated series Legion of the Super-Heroes and instead of leader of the Five he is a member as the Empress is the leader. Tharok clashed with the Legion a few times throughout the series. Tharok was partially responsible for putting Saturn Girl in a coma. Years later, Imperiex freed the prisoners of Takron-Galtos.
The Five journeyed back to Earth and helped destroy the Legion. They were all returned to prison except for Validus, who became Imperiex' chief enforcer. Empress was rendered powerless after Matter-Eater Lad ate part of the Eye. Their team disbanded as they were absorbed into Imperiex forces.
Justice League vs. the Fatal Five
Tharok appeared in the 2019 movie Justice League vs. the Fatal Five as a member of the Fatal Five and a major antagonist. Tharok attacked the Legionnaires headquarters with Mano and the Persuader and stole their time machine with Star Boy stowing away. Arriving in the 21st century, the three were descending into Earth when Star Boy activated a fail-safe inside the device that froze the villains for many months. After being freed from their prison, Tharok attacked Superman and Mister Terrific transforming his robotic arm into a plasma cannon before escaping with the others. Tharok, Mano and Persuader later attacked a small town to draw out the Green Lantern Jessica Cruz but Star Boy and the Justice League arrived and Tharok chased Cruz into the sky before giving up and escaped.
Alexis Luthor| Blight | Brainiac | Composite Superman | Computo | Controllers | Cosmic King | Dark Circle | Darkseid | Dominators | Drax | Emerald Empress | Evillo | Fatal Five | Glorith | Grimbor | Hunter | Infinite Man | Justice League of Earth | Khunds | Legion of Super-Villains | Leland McCauley | Lightning Lord | Mano | Mordru | Nemesis Kid | Ol-Vir | Omega | Persuader | Pulsar Stragrave | Ra's al Ghul | Roxxas | Saturn Queen | Sklarian Raiders | Starfinger | Sun-Eater | Superboy-Prime | Taurus Gang | Tharok | Time Trapper | Tyr | Universo | Validus | Vandal Savage | White Triangle