When Kal-El was rocketed to Earth to escape the destruction of Krypton, the city of Argo would also manage to survive (at least, for a while). However, Argo City experienced its own calamity and Kal-El’s cousin Kara Zor-El was sent to Earth to be together with family. Kara would adopt the mantle of Supergirl, Superman’s secret weapon in his war on evil. Kara would also adopt the identity of Linda Lee, an orphan in Midvale eventually going on to live with Fred and Edna Danvers (taking their name). Supergirl would become a great hero in her own right and would give her life during the Crisis on Infinite Earths. A new version of Supergirl would emerge less than three years later in the comics as an artificial construct of the Lex Luthor of an alternate reality pocket universe named Matrix (modeled after Lana Lang). Made to combat General Zod and his minions Faora and Quex-Ul who escaped the Phantom Zone, Matrix would fail and recruit Superman for help. Superman would likewise fail against the villains who wiped out all life on that Earth. As they threatened to do the same to Superman’s Earth, he was forced to kill them as Matrix would accompany him home. Making a life for herself in her new world, Matrix would eventually merge with a dying girl named Linda Danvers becoming an Earth-born angel. Eventually, Linda would retire only to become trapped in Hell. Another Supergirl would emerge in Cir-El who was a girl named Mia that Brainiac intermingled with Kryptonian DNA and implanted with false memories of being Superman’s daughter from the future. She would eventually sacrifice herself to stop Brainiac. Another Supergirl would emerge this time returning her to her Kara Zor-El roots only for her origins to change again following Flashpoint. DC Rebirth would alter her origins yet again.
The twin brother of J’onn J’onzz (where twins are exceedingly rare on Mars) whose name means “darkness in the heart,” Ma’alefa’ak followed in his father’s footsteps as a scientist as J’onn became a Manhunter like their mother. Mars would see its world altered forever when the planet Apokolips invaded and perverted Ma’alefa’ak into a disciple of Darkseid. Seeking out components of the Anti-Life Equation in the minds of those on Mars against their will (comparably to rape for their culture), Ma’alefa’ak would be found out where he murdered his mother and was taken into custody by his brother. His memories altered and telepathy disabled (the most brutal punishment next to death in their culture), Ma’alefa’ak returned to life as a scientist but was driven mad by being unable to touch the minds of those around him. In response, he crafted a plague called H’ronmeer’s Curse that made Martians burst into flames should their minds meld. All life on Mars would be wiped out save J’onn (who witnessed his wife and daughter die) and his twin. Enraged, J’onn believed he killed his brother and walked the face of a barren Mars alone for centuries. J’onn would accidentally be teleported to Earth as Ma’alefa’ak, who survived and instead believed his brother to be dead, would learn of J’onn’s emergence on Earth decades later and followed him to destroy his life all over again. The brothers would fight and J’onn sent Ma’alefa’ak into the sun where it’s believed he met his demise. Post-Flashpoint, Ma’alefa’ak is a Red Martian manifestation in J’onn’s mind. For Young Justice, Miss Martian is Martian Manhunter’s niece, the daughter of J’onn’s sister, and Miss Martian has twenty-nine siblings and 300 cousins.
When Dick Grayson would retire from being Robin, Batman would happen on a youth stealing the tires off of the Batmobile. Named Jason Todd and an orphan whose father was killed by Two-Face, the boy was sent to a home for troubled youth only to uncover it was a front for a thief network. Batman and Todd would bust up the ring leading to the Dark Knight taking the boy on as a protege and partner in a new Robin (in hopes of channeling his immense rage such that he doesn’t become a criminal). At one point, Todd would learn about his father’s death at the hands of Two-Face and sought to slay the villain for the crime. Batman would stop him, trying to convince the boy to abandon vengeance only to become the first in a series of issues involving Todd. The boy became reckless and anger prone, breaking Batman’s taboo about firearms and perhaps even murdering a criminal (though Todd claimed the villain slipped and fell to his death). Todd would eventually learn that his biological mother was alive and sought her out only to learn she’s in the employ of the Joker and she handed him over to be brutally murdered. The events of Infinite Crisis would resurrect Todd who was angered to learn Batman did not kill the Joker for his murder. The youth would spend years traversing the globe preparing to get revenge on both the Joker and Batman eventually adopting the identity of the Red Hood (the Joker’s identity prior to his clown-like transformation). As the Red Hood, Todd tried to takeover organized crime in Gotham City from the Black Mask as part of a scheme to be a better guardian for the city than Batman (controlling crime rather than trying to stop it) that ended with a confrontation between Todd, Batman, and the Joker where the Clown Prince of Crime tried to blown up all three. Later, Todd would emerge in New York City as Nightwing trying to show his superiority to his spiritual big brother by killing criminals rather than arresting them. When the two are forced to work together, Todd abandons the identity and would again don the Red Hood as a member of the Earth-hopping Challengers from Beyond (at one point adopting the identity of Red Robin). When Batman apparently died, Todd became a murderous version of his mentor terrorizing Gotham City. Eventually, Todd would abandon this pursuit as Grayson became Batman and Batman’s biological son Damian became Robin leading to Todd again becoming Red Hood and again leading a deadly war on crime. Following the events of Flashpoint, Todd’s origins were re-imagined as a youth who attracted the attention of the Joker who felt he could manufacture the child as a new Robin for Batman such that he could later kill the child to hurt his foe. Events mostly played out the same save that he was resurrected by Talia and the Lazarus Pit eventually joining the League of Assassins. Later, he would form a mercenary team called the Outlaws with Roy Harper and Starfire. Eventually, Todd would join Batman, Incorporated as Wingman with Damian as his partner Redbird until the child’s demise. Following DC Rebirth, Todd’s previous origins are intermingled as he forms a new Outlaws team with Artemis and Bizarro. A memorial hologram of Jason Todd is visible in the second season of Young Justice.