Who's Who: Cosmic Boy

Cosmic Boy

Real Name: Rokk Krinn

Super-Power(s): Magnetism
Planet of Origin: Braal

Legion Seniority: He, Saturn Girl, and Lightning Lad were the three founders of the Legion. 

Traditionally he is considered the First Legionnaire.

Legion Log 
Cosmic Boy made his debut in Adventure Comics #247 and was an active member until he resigned in Legion of Super-Heroes (vol 3) #12 to help run the Legion Academy and to help train young would-be Legionnaires.
Cosmic Boy was the first Legion Leader, serving in their first and second years. 
Cosmic Boy was everybody's friend, and lived up to the nickname "the Rokk of the Legion." He was especially close to fellow founders Lightning Lad and Saturn Girl. Lightning Lad was his best friend.
It was eventually explained that Cosmic Boy was leaving his home planet Braal to try to make money on Earth when he met up with fate. So he looked upon the Legion as not just something important, but in very real terms, as his job.
Cosmic Boy, Lightning Lad, and Dream Girl are the only Legionnaires to have siblings also join the Legion. Lightning Lad's twin sister joined first as Lighting (Light) Lass, followed several years later by Dream Girl's younger sister The White Witch. Finally, another few years later Cosmic Boy's younger brother joined as Magnetic Kid.
Cosmic Boy was romantically involved with Night Girl (Lydda Jath) from the Legion of Substitute Heroes. 
Cosmic Boy is a history buff. He enjoyed visiting the past, and was especially pleased to meet Batman when the Caped Crusader accidentally traveled into the 30th Century (The Brave & The Bold #179).
During the five-year gap following the Magic Wars, Cosmic Boy lost his powers in the Braal-Imsk conflict, in which the Imskian army used a "dampener" on the magnetic fields within the Braalian soldiers. No longer using his codename, 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).
After the five-year gap, a powerless Cosmic Boy joined the new Legion, proving that he needed no powers to be a hero. Rokk did however regain his powers shortly before Zero Hour, 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. After learning that he was apparently destined to become the Time Trapper, Rokk and the rest of the Legion were erased from history by Zero Hour. 
Cosmic Boy was also one of the members of the SW6 Legionnaires, and appeared in Legionnaires when it was spun-off into its own series.
After the Reboot, Rokk Krinn came from a poor family but became a superstar in the Braallian sport of Magnoball, earning the nickname "Cosmic Boy". After being rescued from his greedy manager by R.J. Brande, he helped found the Legion and was appointed its leader. In this continuity, he was initially romantically involved with Saturn Girl, and later with Quantum Kid II.
After the Threeboot, Cosmic Boy is leader of the Legion until voted out of office after sending the Dominator world to the Phantom Zone. He is later recruited by a time-traveling 41st-century superhero team.
After Infinite Crisis, Cosmic Boy's original history has more or less been reestablished. 
Cosmic Boy has appeared in the Superman Animated Series, voiced by Chad Lowe; the Legion of Super-Heroes animated series, voiced by Wil Wheaton; and Smallville, played by Ryan Kennedy.

Important Cosmic Boy Stories: 

Adventure Comics  #247

(reprinted in Legion of Super-Heroes Archives Vol. 1)

The debut of Cosmic Boy AND the LSH!

Superboy/Legion of Super-Heroes #215 

 (reprinted in Legion of Super-Heroes Archives Vol. 12)

Cosmic Boy lays his life on the line for his pals...in his sexy new uniform!


Legion of Super-Heroes Annual #1 (1982)

(reprinted in The Great Darkness Deluxe Hard-Cover Edition)

 Cosmic Boy changes his costume again

Legion of Super-Heroes (v2) #297

Nuclear terrorists deal Cos a terrible blow!

Legionnaires 3 mini-series

The bond of trust & affection between the founders is highlighted.

Cosmic Boy mini-series 

Cos and Night Girl stumble upon the Time Trapper's most nefarious plot

Legion of Super-Heroes Annual #3 (1987)

Cos is part of the re-constituted Substitute Heroes

Legion of Super-Heroes (v4) #1 (1989)

Though powerless, Rokk Krinn rejoins the Legion, "5 years later"

Legion of Super-Heroes (v4) #59-61, Legionnaires #16-18 (1994)

Unhinged by Earth's destruction Cosmic Boy attempts to put it back together, culminating in the merging of the LSH with SW6, the revelation that he will become the Time Trapper, and the "reset" of this section of the timestream

Legion of Super-Heroes (v4) #0 (1994)

 

The rebooted origin of Cosmic Boy

Legion Worlds #3 (1994)

 

Living on the streets of Braal, Cosmic Boy runs afoul of Magno and rebuilds the Legion

Supergirl and the Legion of Super-Heroes #30 (2007)

Threeboot Cosmic Boy does the unthinkable and takes out the Dominator homeworld

Legion of Super-Heroes (v7) #13 (2012)

 

Cosmic Boy battles pirates from his home planet of Braal

Superman The Animated Series "New Kids in Town" (1998)

Cosmic Boy, voiced by Chad Lowe

Smallville "Legion" (2009)

 Ryan Kennedy as Cosmic Boy