Trogaar is a one-shot villain in the Teen Titans series. He is notable for being the first villain that the Teen Titans defeated and the one who is responsible for the Teen Titans being formed. He is a Gordanian prison ship ruler who brought Starfire to Earth. Trogaar serves as the main antagonist of Teen Titans origin story episode Go!.
After Gordanian invasion of the planet Tamaran, which ended with the planet's princess, Koriand'r, or Starfire, was taken prisoner, Trogaar was given the task of delivering to the Citadel so she can live out the rest of her life as a slave. However, a furious Starfire escaped from Trogaar's ship despite his soldiers' attempt to stop her, and fled to the nearby planet Earth. Trogaar then had his ship follow to the town of Jump City where she landed, then he planted a device on a small island, that projected a hologram of him that he used of the broadcast a message to the people of Jump City. The message told them about they are looking for Starfire, saying that she is a dangerous prisoner, telling them not to interfere and they will leave the city with only minimal damage, but he also gave a warning that if they help Starfire, their destruction will be absolute.
Despite Trogaar's threat, Robin, Cyborg, Beast Boy, and Raven located Starfire, and helped her fight of Trogaar's soldiers when they attempted to recapture her, before they returned to Trogaar's ship. Trogaar then became enraged by this, and decided to destroy Jump City as punishment for helping Starfire, using the weapon on his ship to do so. However, Robin, Starfire, Cyborg, Raven, and Beast Boy snuck aboard Trogaar's ship to stop him from destroying Jump City right when the weapon was fully charged.
They defeated most of Trogaar's men before Cyborg and Starfire fought Trogaar before overpowered them. When Trogaar and his men surrounded Robin, Cyborg, and Starfire, Raven used the full extent of her powers and destroyed Trogaar's ship leaving his men unconscious. However, Trogaar was still standing and attempted to attack her and Beast Boy, but was knocked out by Cyborg using his newly created sonic cannon.
Afterwards the five heroes formed the Teen Titans, but it is unknown what happened to Trogaar and his men.
Although Slade is the main antagonist of the series, Trogaar serves as the Heavy of the series because without him, Starfire would never have been brought to Earth and the Teen Titans would have never formed.