Young Justice: Outsiders has changed the face of its universe in a big way, with six separate superhero groups now working together in secret to fight the villainous group known as The Light. The cast of Young Justice features dozens of characters, with more being introduced each season. This leads to a lot of changes in the various team line-ups, even ignoring the years that pass in-universe between seasons.
The third season premiere opened with a mass defection, as several superheroes led by Batman resigned from the Justice League due to their dissatisfaction with how the team was addressing the issue of metahuman trafficking. However, it was later revealed in episode 8, "Triptych", that the resignations were a ruse and that Batman, Nightwing, and Robin were still in contact with the rest of the Justice League's leadership. Now the Justice League has been secretly broken into six teams, all coordinated by master-hacker and strategist Oracle, tackling the operations of The Light from multiple angles.
The following breakdown will profile every individual member of the six hero teams that have formed or changed membership so far on Young Justice: Outsiders. In the case of newer characters (like The Spoiler and Orphan) who have not had their backgrounds explored on the show yet, their backstories in the comics have been briefly described. It is hoped that this will give fans of the show who aren't that comic savvy some insight into these new heroes.
Justice League - Earthbound
In order to repel an invasion by the alien Appellaxians, seven heroes joined forces to save the world. Realizing there was strength in numbers, they formed a Justice League to organize the superheroes of Earth into one body that could fight for truth and justice on a global scale. Now overseen by the United Nations, the League's ranks stand diminished as half of the team is working off-world and half of the League members on Earth publicly resigned in the wake of increasing bureaucracy limiting their ability to do good.
- Aquaman (Kaldur'ahm) - A master of Atlantean sorcery, the former Aqualad has taken up his mentor's title as Aquaman, allowing Arthur Curry to focus on his duties as King of Atlantis. He has also taken up a co-chair role, leading the Justice League's forces on Earth.
- Doctor Fate - A symbiotic hero formed whenever someone dons the magical Helmet of Fate, Doctor Fate's actions are largely controlled by Nabu - the Lord of Order whose power is contained within the ancient helmet. Nabu's current host is the wizard Giovanni Zatara.
- Black Canary (Dinah Lance) - One of the world's greatest martial artists, Dinah Lance also has the metahuman ability to release focused vocal blasts of sonic energy - i.e. The Canary Cry.
- Captain Marvel (Billy Batson) - Granted amazing magical powers because of his noble heart, Billy Batson is transformed into Captain Marvel whenever he says the word Shazam!
- Steel (John Henry Irons) - A brilliant engineer who was inspired by Superman's example, John Henry Irons built a suit of armor and a special hammer to become an entirely new Man of Steel.
- The Flash (Barry Allen) - The self-described Fastest Man Alive, being married with children (twin toddlers who have inherited his super-speed) hasn't slowed The Flash down at all.
- Rocket (Raquel Ervin) - The young woman who convinced Augustus Freeman to become Icon, she also became his partner, armed with a belt that allows her to generate bubbles of kinetic energy.
- Zatanna Zatara - A powerful magician who casts her spells by speaking backward. Daughter of Giovanni Zatara and mentor of Thirteen.
- Red Tornado (John Smith) - Originally created to destroy the Justice League, this wind-manipulating robot wound up turning on its creators and joined the World's Finest heroes.
- Fire (Beatriz da Costa) - A Brazilian spy who gained the power to generate green flames after being caught in an explosion. She was recruited into the Justice League sometime between season 2 and season 3. She has not appeared on-screen yet, but it was said that she designed GeoForce's fire-proof costume in "Evolution."