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Cosmic Boy src

Rokk Krinn is a founding member of the Legion of Super-Heroes under the code-name Cosmic Boy. Rokk is a Braalian and like all of his native race has the superhuman ability to generate magnetic fields.

Early Life

Though Rokk is a Braalian, he was not born on Braal; he was born on Earth before his family moved back to Braal. This is why he has more control over his magnetic abilities than other Braalians.[1]

Rokk's parents were struggling for work on the impoverished world of Braal, so he left at the age of fifteen for Earth to find work to assist his family. On a spaceship trvelling to Earth helped save billionaire R.J. Brande from an assassination attempt along with Lightning Lad and Saturn Girl.[2]-[3]

The Founding of the Legion

Brande was so impressed with the teens' bravery, that he petitioned the United Planets to form a Legion of Super-Heroes – an ever-growing cosmic team inspired by the exploits of 20th century teen super-heroes Superboy and Supergirl. Rokk became became Cosmic Boy, the team's first leader. Eventually they would travel backwards in time to the 20th Century to meet Superboy and Supergirl and welcome them into their ranks.[4]-[5]-[6]

During his first year worked as a leader dedicated and being a figurehead as a founding member and the first leader even when just another active member. After sometime, a romance blossomed between Lydda Jath alias Night Girl of the Legion of Substitute Heroes.

After time he raised enough funds to bring his family to Earth, but a firebomb went off in the neighbourhood where they lived. His whole family was injured and his mother later died. This led Rokk to almost kill this also encouraged his younger brother, Pol Krinn, to join the Legion Academy as Magnetic Kid. When he agreed with his fellow founders that they were getting old and it was time they resigned, Rokk was pushing for his brother to be elected to the team in his place.

He would go on to found a second Legion of Substitute-Heroes with Lydda and the Legion Academy instructors and mourned his brother when he sacrificed himself during the Magic Wars.

Crisis on Infinite Earths

 Main article: Crisis on Infinite Earths

Although the Legion survived the Crisis mostly unscathed, the Time Trapper took advantage of the chaos to isolate and weaken the Legion, making them believe her fellow Superboy wasn't the real one and forget about her recently fallen member Supergirl. In a trip to the past, Cosmic Boy meets Superman and is shock that his childhood friend doesn't recognize him.

Five Year Gap

 Main article: Five Years Later

After the Magic Wars, he lost his powers in the course of a war between the planets of Braal and Imsk (the homeworld of Shrinking Violet), in which the Imskian army used a "dampener" on the magnetic fields within the Braalian soldiers. "Vi" was on the scene when her fellow Legionnaire was crippled by the dampener during the battle of Venado Bay, and harbored deep guilt for years. Now going by plain old "Rokk Krinn", Rokk retired to the slums of a demilitarized Braal with his wife Lydda, who gave birth to their son "Pol" (named for Rokk's brother).

When Reep Daggle, the former "Chameleon Boy," reformed the Legion, a powerless Rokk joined up, moving his family to the Legion's new headquarters. The former "Cosmic Boy" continued to serve with honor during the adult Legion's tour of duty, proving that he needed no powers to be a hero. Rokk did however regain his powers shortly thanks to a special pair of power gauntlets. He took on the codename "Polestar", only to renounce the power gauntlets after they began to affect his mind.

Zero Hour

 Main article: Zero Hour

Shortly after a cosmic crisis brought back by a Hal Jordan mind-controlled by Parallax put the whole space-time continuum in danger. Rokk learned that he was apparently destined to become the Time Trapper before he and the rest of the Legion were erased from history.

Post-Infinite Crisis

 Main article: Infinite Crisis

Nevertheless, the events other Crisis unleashed by Superboy Prime and Alex Luthor restored the Legion with a slightly altered history as evidenced by the trip of six Legionnaires to the time present. Once again, Garth, Imra and Rokk formed a super-hero team backed by RJ Brande[7] and travelled back to the past to induct Superboy.[8] They also recruited the next Superboy, and inducted Supergirl into the team when the Kryptonian girl landed in the 30th century.[9]

Superman and the Legion of Super-Heroes

 Main article: Superman and the Legion of Super-Heroes

Unfortunately, xenophobia started spreading through the galaxy because of manipulations of the Time Trapper and the efforts of Earth-Man. The Legion agreed the future was becoming too dangerous for Superboy and they would not visit him again after the war against the Anti-Monitor.

The witch hunt led by Earth-Man and sponsored by the Earth Government forced the Legion's founding members to go underground. Cosmic Boy tried to keep the team together, but it was getting increasingly hard. The conflict was also taking a toll on his friends and co-leaders. Garth and Imra's children went missing and Garth was forcefully separated from his sister. As a result of it, Garth became very short-tempered and snappy and Imra was more passive for a while.

Their situation started to look up when Superman returned and rejoined the Legion and they took Earth-Man down together.

Legion of 3 Worlds

 Main article: Final Crisis: Legion of 3 Worlds

But although Earth-Man had been defeated, tension between the Legion and the United Planets was still high, with the UP Government looking to shut the Legion down.

Superboy-Prime ending up in the 30th century and freeing the Legion of Super-Villains forced the Legion to recall Superman and bring two Legions of different timelines to her own universe. Rokk found herself teaming up with two different Cosmic Boys.

During the battle, Cosmic Boy, Saturn Girl, Lightning Lad and Superman were taken to Vanishing Point by the Time Trapper. Before managing to knock him out, the four heroes saw he was an older Superboy-Prime. Brainiac 5 hypothesized the identity of the Time Trapper is ever-changing because he is a sentient timeline trying to erase theirs.


  • Braalian Physiology: Cosmic Boy is a Braalian, who have the natural ability to lift and manipulate metal. However, his knowledge and control over magnestism is much greater than the average Braalian. Cosmic Boy's magnetism can produce a number of astounding effects.
    • Magnetic Manipulation: He has the ability repel, attract, and manipulate metal objects of varying sizes, or anything containing metal, even on a microscopic scale. Naturally, the more metal there is in an object, the easier it is for him to affect it magnetically. Cosmic Boy has achieved the feat of pulling large iron meteors and satellites down from space to the surface of the Earth with minimal effort, as well. He once exerted "every bit" of his power to draw thousands of iron chunks upward into space.
    • Magnetic Force-Fields: Cosmic Boy can protect himself from physical harm, can stretch his fields to protect a large group, and can suspend persons or objects in the air using magnetic force fields. His force fields have also been able to withstand nuclear blasts.
    • Magnetic Flight: Cosmic Boy can suspend himself in flight by riding the Earth's magnetic field.
    • Electromagnetic Sight: By concentrating, Cosmic Boy can perceive the world around himself solely as patterns of magnetic and electrical energy. He can perceive the natural magnetic auras surrounding living beings, as well.
    • Magnetic Pulse: Cosmic Boy can focus his magnetic energy into immensely powerful concussive blasts. He can also overload or short-circuit electrical systems.
    • Energy Absorption: Cosmic Boy has been shown absorbing some forms of energy through his magnetic force fields to temporarily boost his own strengths. Early in his career with the Legion, he absorbed Lightning Lads's lightning blast.
    • Geomagnetic Link: Cosmic Boy is tied very closely to Earth's or what ever planet he is on EM Field. As is it effected, so is he. He knows instinctively all that happens to it.


  • Enhanced Intellect: Cosmic Boy is from the 30th Century, and as such his intellect is a level 9, compared to the average level 6 intellect of someone from the 21st Century.
  • Leadership: Cosmic Boy is a charismatic and effective leader, as seen during his successful tenure as the Legion's first leader.


  • Non-Metal Materials: Cosmic Boy's power cannot affect non-metals, such as organic substances like wood.



  • Cosmic Boy is one of the few Legionnaires ever to have his own miniseries, which ran for four issues in the mid-1980s as a spin-off of the Legends cross-over.



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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.

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This character is exclusive to the continuity of the original Legion of Super-Heroes universe and its variations.
The original LSH universe and its variations are from between their first appearance to Zero Hour and from Lightning Saga and beyond. Any official designation for the home universe for this character has not been given, and thus this page may have to be moved in the future. In the meantime, it's designated as "Pre-Zero Hour".