The Teen Titans animated series introduced audiences to a number of classic DC heroes and villains, ranging from well-known to genuinely obscure. But it also introduced some new characters to that particular version of the universe, including the fan-favorite thief with a surprisingly noble heart, Red X.
Since this mystery hero is about to make his way into the DC Universe as part of DC's Future State event, we're taking a look back at Teen Titans' Red X and how this minor villain remained at the center of an unsolved mystery that could make its way into the DC Universe.
Red X was introduced in the episode of the same name from the first season of Teen Titans. A sleek new criminal in Jump City, Red X was a genuinely dangerous tactician and fighter, quickly dispatching Raven, Beast Boy, Starfire, and Cyborg whenever he encountered them. Clad in a full black suit with a skull mask, a torn cape and a distinctive red X across his chest, Red X proved almost impossible to catch by the Teen Titans, largely thanks to his most versatile tool -- a minor teleporter powered by the volatile element Zynothium that gives him unpredictable speed the heroes couldn't match. Eventually, Red X did well enough to impress the likes of Slade and earned an audience with him. It was revealed Red X was actually Robin undercover to try to get close to the villain.
This resulted in the Teen Titans growing distrustful of Robin for a time, especially considering he'd used his time with them to develop strategies to defeat them -- just like his mentor Batman has done to the Justice League. Robin turned away from the identity and swore to never use it again. But not long after, the costume was stolen by a mysterious individual. Seeking more Zynothium to fuel the suit, Red X hunted down Professor Chang -- the scientist Robin got the initial supply from -- in the third season episode "X." When Chang eventually kidnapped most of the Titans, Robin was forced to work with Red X to save his teammates. Although they were successful -- and Robin was able to steal the teleporter from him -- Red X was able to make his escape.
Red X only appeared in one more time in the Season 5 episode "Revved Up," after briefly cameoing as a member of the new Brotherhood of Evil. Initially shown as one of the competitors in the race for a stolen briefcase containing something secret and valuable to Robin, he turned against the other villains after Robin saved his life from a crash. Red X has only appeared since then in shorts or Teen Titans Go!, but remains a fan-favorite. Ever since his first appearance in "X," the question of the new Red X's secret identity has haunted the Teen Titans fandom. Even in-universe there are a host of theories, ranging from the enticing idea that Red X is Jason Todd (a theory floated repeatedly by Beast Boy) to more absurd concepts like that he's a cybernetically-enhanced monkey.
Red X's design, mystique, and unique tech all combined to make him one of the more enigmatic elements of the animated series. His surprisingly noble side and brief moments of teamwork with Robin suggest he may not be a complete villain after all.
While the animated version might remain unknown, it appears at least one version of Red X will be making his way to the DC Universe of the comics, where the character is slated to appear among the other prominent future heroes of DC's upcoming Future State. Potentially, he'll have his true identity revealed over the course of that story-arc, possibly giving closure to a fandom mystery that's been around since before Teen Titans originally ended all the way back in 2006.