Malchior is first mentioned in a book read by Raven. In the book, Malchior faces the wizard, Rorek of Nol. The dragon was more superior to Rorek, so Rorek trapped Malchior inside his spellbook with a powerful curse. Raven later owned the book sometime ago. When Raven wanted to stay alone to read the book, Malchior made his move. He tricked Raven into believing that the roles in the battle were reversed, that he was the wizard and Rorek was the dragon. He told Raven that he could empathize with her nature. He gained Raven's trust and affection and manipulated her in freeing him from his imprisonment in the book first, then he taught her his full knowledge of his magic to ensure that he will be fully freed.
Raven succeeded in breaking the curse, but to her horror she realized what she unleashed. When the Titans were unable to take Malchior down in combat, Raven trapped Malchior in the book again and locked it away.
Some time later, Malchior was somehow freed and was recruited into the Brotherhood of Evil in his paper form, but he can turn into a dragon at will. During the final battle with the Titans, Malchior planned to burn Melvin, Timmy Tantrum, and Teether that Raven recruited in the battle, but his attack was foiled by Herald who blew his horn and sucked in the fire and then Malchior himself to another dimension.
It is unknown what happened to Malchior afterwards.
Powers and Abilities
While trapped in the book, Malchior had limited powers but he could remodel the pages at will. In his humanoid paper form, he could employ his magic powers to further extent. In his true dragon form, Malchior possessed super strength, physical endurance, the power to fly with wings and to breathe fire. He also possessed great resistance to physical, energy and magical attacks. In all three forms he possessed great knowledge of dark magic ever known to anyone.
Malchior is the only dragon to be seen in the show.
Malchior is a symbolic villain on the grounds that, according to the show's writers, the episode that he first appears in and does the most in, 'Spellbound", was meant to be a subtle warning to kids (the show's main audience) about the dangers of Internet chatrooms. Indeed, many of the ways that Malchior manipulates Raven are extremely similar to the ways that Internet predators manipulate potential victims, such as him early on leading her to believe that he's the only one who "understands" her, as well as of course him lying to her about who (or, in this case, what) he truly was.
Evil Dragon and other dragons in the Night Shine Planet are also dragons in Teen Titans.