- "I'm no hero. I'm a husband, and if this is the end then I have to be with my wife and kid. I'm sorry."
- —Ryan Choi [src]
On the Earth of Earth-1, Dr. Ryan Choi was a former physics professor, the husband of Amanda, and the father of Simone. On the Earth of Earth-Prime, he is the father of Simone. He is the Paragon of Humanity, and was one of the seven known living individuals to have survived the destruction of the original multiverse, along with Barry Allen, Kate Kane, Kara Danvers, Sara Lance, J'onn J'onzz, and Lex Luthor, until they recreated the multiverse with the help of Oliver Queen.
On December 10, 2019, six months after Simone birth, Ryan was in Ivy Town on the phone with his wife when he was approached by Ralph Dibny, Iris West-Allen, and Dr. Ray Palmer (who Ryan was a big fan of). The three explained that they were there because Ryan was meant to be the Paragon of Humanity, one of seven heroes who could save the multiverse from being destroyed by the Anti-Monitor. Ryan does not believe them at first and decides to leave to be with his wife and daughter. Iris eventually convinces him to help, and he is brought aboard the Waverider. Once back on the waverider, the heroes are greeted by Harbinger, who has returned after mysteriously disappearing. Pariah also appears and the heroes realize that Harbinger's return is a trap by the Anti-Monitor, who proceeds to kill Mar Novu and destroy Earth-1. Knowing what must be done, Pariah sends the 7 Paragons to the Vanishing Point where the Anti-Monitor can't reach them as the waverider is destroyed and remaining heroes killed by the antimatter wave. At the vanishing point, the paragons witness Superman disappear and be replaced by Lex Luthor who used the Book of Destiny to make himself the Paragon of Truth.
Ryan was looking after his daughter, Simone when a shadow demon came to his house to attack him, he is almost killed, but Sara saves him. Later at the bunker, he comes up with the plan to send Mobius to the Microverse.
Initially, Ryan had a lot of doubt in himself. He did not want to believe he was a paragon of anything. However, after spending a month stuck with the other paragons, and receiving a few pep-talks, he began believing in himself. He begins opening up and trusting of his new friends.
He is also open to trying new things. He was excited at the opportunity of walking on an alien planet and was excited when Barry Allen showed off his speed.
- Genius-level intellect: Ryan Choi has the intellect to understand Dr. Ray Palmer's research on sub-atomic density manipulation, and teach fundamental physics.
- Expert tailor: According to Nora he was the one who made Barry's sixteenth suit.
- Expert Technician/Engineer: He and Lex Luthor were able to build and re-engineer some of the Time Masters tech from the Vanishing Point.
- Indomitable will: Ryan Choi is a Paragon, meaning he is a being of the purest will.
- Hand-to-hand combat: Ryan has some hand-to-hand combat skills as he was seen defeating Shadow demons with just that.
DC's Legends of Tomorrow
Crisis on Infinite Earths
- Ryan is most likely the founder of Choi Enterprises, although it's unconfirmed.
- Ryan is the only human civilian to be chosen as a paragon while everyone else is a vigilante, a trained assassin, a terrorist, a meta-human, or a powered alien.
- Ryan's daughter, Simone, might be named after one of Choi's comic book creators, Gail Simone.
- Ryan shares his last name with Grace Choi, the girlfriend of Anissa Pierce.
Behind the scenes
- In the DC Comics, Ryan Choi was a student of Ray Palmer and his successor to the identity of the Atom. His first appearance in the comics was Brave New World #1 (August, 2006).