Mal first met the Teen Titans when they helped him fight a street gang. They asked him to join and he said yes. Later he called himself the New Guardian. After having a vision of angels and gaining a magical horn, he decided to take up the name Hornblower. Then the horn somehow vanished so he went back to being the New Guardian. When the Teen Titans disbanded he retired from being a superhero. He married former Titan Bumblebee and is a successful writer.
During the Infinite Crisis, Donna Troy gathered together a team of heroes to deal with an anomaly in space. Mal and Bumblebee were among those to be recruited.
After the space travelers were hit with dangerous cosmic energy, Mal tried to open a portal to safety with his horn. However, the sub-sonic weapon blew up in his face and Red Tornado exploded, resulting in pieces of metal getting lodged into his chest. After nearly dying in a hospital, his vocal chords and lungs were replaced with circuitry. Unable to speak, Mal assumed the codename Vox and found his dimension-opening Gabriel Horn was now a part of him.
During the missing year after infinite crisis Mal (now as Vox) and Bumblebee join the Doom Patrol. He was part of the team that fought the Brotherhood of Evil alongside the Teen Titans.
He has recently appeared as an ally of Geode, Geo-Force's ex wife. He used a horn similar to his old one to get Geo-Force and The Eradicator away from the Markovian palace. It Appears he has joined forces with Geode to get revenge on Looker,a member of the Outsiders.
Weight: 179lbs (as Titan) 256lbs (now)
As Guardian, he wore an exoskeleton that gave him super strength. As Hornblower he carried a horn which could teleport himself and others and help in battle.
In Other Media
Malcolm made an appearance in the 5th season of Teen Titans. He was in the episode: "Calling All Titans" and "Titans Together," going by the name Herald and was from another dimension. He was voiced by Khary Payon.
Mal Duncan first appears in episode 10 of Young Justice, 'Targets'. We see him at Miss Martian and Superboy's new school where he appears to be one of the most popular, or at least most respected, person there; Superboy is commended for facing up to him, though not a very clever move to make apparently. It also appears that Mal is dating, a Bumblebee cheerleader, Karen Beecher. He later appears in Episode 18 "Secrets" at a Halloween party dressed as Superman.
Following the five year time skip, Mal is seen as part of the team in season 2. He does not play an active role at first, instead serving as the mission operations director from Mount Justice. His relationship with Karen also grows strained during course of the season. In the episode "Cornered", Mal becomes the new Guardian during a battle with Despero at the Hall of Justice.
He begins playing a more active role in the team following this, including being part of the Team that infiltrated and disabled Mongul's Warworld.
He is voiced by Kevin Michael Richardson.