Universo is a native of the 30th/31st century and a constant enemy of the Legion of Super-heroes and had plagued the Legion in their different incarnations. A villian capable of hypnotize his victims, Universo has been very close to conquer earth several times.
As a Green Lantern, Universe possesed the wide range of powers than it came with the use of a power ring. Universo lost this powers when he was stripped of his ring and rank. However he was able to use hypnotism over his victims. This power is so strong than can affect the population of a whole planet.
Original Legion (Silver/Bronze Age )
As a member of the Green Lantern Corps in the latter part of the 30th Century, Vidar was sent to Earth to stop certain experiments that had the potential to reveal the secrets of the birth of the universe. Tantalised by the possibility of learning these secrets and gaining powers equal to those of his masters - the Guardians of the Universe - Vidar turned renegade.
Stopped in his tracks by the Legion of Super-Heroes, Vidar was turned over to the Guardians for justice.
Years later, he returned to Earth under the guise of Universo, and used the power of super-hypnosis to try to conquer the planet. At one stage he even managed to have the Legion of Super-Heroes outlawed, and turned the populace of the world against them. Universo's attempts to conquer the Earth were only prevented by the Legion when they were aided by his son Rond Vidar. As a reward for his efforts, the Legion made Rond an honorary member.
Post Crisis Universe:
The Universo Project
After abducting several individual of stronger minds throught the know universe, Universo took control over the earth behind the figure of Earth President, and put the population of earth, including several members of the Legion itself, under his command. Saturn Girl, one of the heroes abducted was capable of free her teammates and together free themselves to thwart Universo plans.
Five Years later (Glorithverse)
In the continuity set after the Magic Wars and the consequent collapse of the United Planets, Universo was among the fighters of the Resistance against the Dominion undercover control of planet earth, becoming an inconvenient ally to the Subs, the resistance force composed by several members of the Legion of Substitutes Heroes. More inclined to use extreme measures to reach the freedom of Earth, Universo helped the Subs and the reformed Legion in the fights against the Dominators. Becoming a war hero for earth population, the ambition of Universo was to become earth's president. The Legionnaries tried to stop the plans of Universo and were partially successful: Universo didn't became earth president, but he won the position of earth ambassador in the United Planets. Universo didn't forget nor forgave this humilliation and his chance of revenge came when he accessed to recordings than showed the Legionnaires acting together with the Khunds. Framing the Legionnaries as traitors, Universo outlawed the Legion in the United Planets space, putting them on the run, a status kept until the event called Zero Hour.
In the continuity reboot set after Zero Hour, Universo was reworked not as Green Lantern renegade, but as a titanian renegade, with his powers working as telepathic cohersion and capable to create illusions to their victims . Captured in the prision of Titan, it would include the forces of the heroes of two eras, the Legion and the Titans to defeat the villian. Universo would return again to attack the Legion, using his telepathic powers to create illusions over the Legionnaires, creating an fictional attack of Darkseid. Saturn Girl was capableof overcome thes illusions and to put Universo in the same ilusion dream where the villian had her prisioner.
When Universo joined Superboy Prime's Legion of Super-Villains he participated in an attack which killed his son, Rond Vidar. Universo tried to claim Rond's Green Lantern ring after Rond's death, but was unsuccessful.