First Red X


 * Red X was originally a fake identity that Robin had conceived in an attempt to get closer to Slade. Mystified by the enigma that the dark villain was presented to, Robin approached Professor Chang for all the necessary items - especially Xenodium for an energy source - to create the Red X costume, and, posing as a superpowerful thief, Robin stole several Slade's computer chips and then offered them as a proposal to introduce a partnership.
 * However, Robin's haste in trying to get too close exposed his identity to Slade, and afraid that if he told his teammates about his plans, they would not play their roles convincingly, thus saying nothing to they. But the plan went wrong; Slade revealed his knowledge of Robin's identity, and while he managed to recover the chips, Slade managed to trick him once again. Robin was back to square one, with an additional step back: he had lost the trust of his friends.

Since the xenodium power core could not be safely disposed of, Robin stored it in a safe in the Tower of the Titans, never to be used again.