DC Database

Jo Nah aka Ultra Boy, hails from the planet Rimbor, is a member of the Legion of Super-Heroes possessing a multitude of powers. However, due to physical limitations, he is only capable of using one of these powers at a time.

He was born on the seedy world of Rimbor and ran with a gang called the Emerald Dragons. Jo was traveling in his Space-speedster when he was swallowed by an Energy-Beast, a giant whale-like creature. They will eat any life-form that happens to fall in their path. Luckily a Galactic Patrol Cruiser saw this and rescued him by slicing the creature open with a ray.

Jo Nah escaped, but his body was charged by the radiation of the beast. He discovered that he could see through anything, even lead. Jo Nah now had various powers, but he could only use it for one super-power at a time. He decided to use these abilities to help law enforcement, earning him the name Ultra Boy and a recommendation to join the Legion of Super-Heroes.

As part of his initiation, Jo Nah traveled with Marla Latham to the 20th Century to learn Superboy's secret identity. Upon success, Ultra Boy was inducted into the team.

He is romantically involved with fellow Legionnaire Phantom Girl. The two began a long-term romance shortly thereafter. Jo Nah often worked alongside Mon-El and Superboy as the Legion's Big Three for their power levels and Jo was once possessed by the spirit of Nero because of it.

Jo Nah later served two terms with the team as the leader. Following his stint as leader, Jo Nah was on the run a second time when he was framed in the murder of his ex-girlfriend, An Ryd. Jo Nah managed to find the real killer, Pulsar Stargrave, but was defeated and believed dead by his hand. In actuality, Jo Nah had been blown through time all the way back to the 20th Century.

He found Superboy and merged minds with him to become Reflecto and returned to the 30th Century. Jo Nah campaigned again for a time as leader but lost and became the deputy to Dream Girl. The coalition did not work and Jo Nah quit.


  • Ultra-Energy Empowerment: Ultra Boy can utilize the ultra-energy in his body in a variety of ways, but only one use at a time. He can change his ultra empowerment at any time almost immediately but he must make a conscious choice first.[2]
    • Ultra-Strength: When Ultra Boy uses this power he is many times stronger than usual. His strength makes him the equal of a Kryptonian/Daxamite athlete of the same height and weight who engages in intense regular exercise.[3]
    • Ultra-Stamina: Ultra Boy could sustain prolonged physical exertion without tiring or undo strain for an indeterminate period of time.
    • Ultra-Speed: Ultra Boy could run at a velocity many times greater than that of a normal human being.
    • Ultra-Breath: Ultra Boy possessed the ability to create hurricane force winds by blowing, and to chill an his breath in order to freeze a target.
    • Ultra-Invulnerability: When using this power, he is impervious to harm by nuclear forces. If propelled at sufficient force, by either his flight ring or being tossed, Ultra Boy can use his ultra-hard body like a human missile.
      • Ultra-Aura: Ultra Boy's ultra-energy radiates an aura, which protects his clothing from being torn when invulnerable, and from burning-up from the friction when traveling at super-speed.
    • Ultra-Flight: Ultra Boy could fly by manipulating a planet's gravitational field. He still requires a Legion Flight Ring for adventures in space.[3] In addition, Ultra Boy rarely uses this power as the flight ring enables the same transportation option while allowing him to use another power.
    • Ultra-Vision: Ultra Boy's penetra-vision makes him able to see through solid matter, this vision power enables him to see through lead, unlike X-ray which is possessed by Superboy and Mon-El. As part of his same ultra-vision power, Ultra Boy can use telescopic vision, in combination with penetra-vision if desired. He also has microscopic vision and is able to analyze fingerprints.He has also demonstrated the ability to see in the dark with Penetra Vision.

Ultra Boy uses his penetra-vision to see through lead.

      • Flash Vision: Another vision-based power, Ultra Boy could project beams of concentrated thermal energy from his eyes. Flash vision works along the same properties as Superman's heat Vision.[4]


  • Mechanical Aptitude: Ultra Boy possessed a passing knowledge of electronic and mechanical engineering.
  • Science: Ultra Boy possessed a small degree of knowledge in the arena of Bio-Physics.


  • One Power at A Time: As mentioned above, one serious limitation to his ultra-powers is that he can only use one at a time. This means that if he wants to fly through space at super-speed he must wear a spacesuit to survive in the cold vacuum. When using his power for super-strength he is not invulnerable and can therefore get tired, feel muscular pain or even pull a muscle.


  • Ultra Boy's name and origin are derived from the biblical figure Jonah, who, like Ultra Boy, survived being trapped inside the belly of a large fish, popularly misrepresented as a whale.

The boy with ultra powers!

  • Ultra Boy was elected leader of the Legion of Super-Heroes in a reader-decided election. The election results favored Ultra Boy with 1,262 votes from a total of 7,810 votes (over 16% of the vote). Ultra Boy served as team leader from 2967-2968.[5]
  • While off-duty, Ultra Boy always retains his invulnerability to guard against surprise attacks.[6]
  • Ultra Boy enjoyed playing 20th Century baseball.



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Legion of Super-Heroes member
This character is or was a member of the Legion of Super-Heroes from the 30th/31st Century, in any one of their various continuities. Including but not limited to, Original Legion, the Reboot Legion, Prime Legion and the Post-Rebirth Legion.
This template will categorize articles that include it into the "Legion of Super-Heroes members" category.