Trigon

Background
The personification of evil, Trigon was a demon lord who destroyed his homeworld by the age of six. Slaying billions of souls in his own dimension, Trigon eventually sired a child by the woman Arella. Their child was Raven, a powerful mystic, who rejected her father's evil and was raised in Azarath, a pacifist community nestled in another dimension.

Trigon tried to breach the barriers between his dimension and Earth's but was stopped by sorcerers from Azarath. Finally tearing through the interdimensional wall, Trigon attacked Earth. Horrified, his daughter Raven agreed to rule by his side if he spared the planet. But she realized her father would not honor the bargain and gathered a group of teenage heroes to stop Trigon's invasion. These heroes were the New Teen Titans and together they drove Trigon into a distant nether universe the Arella agreed to guard for eternity.

Trigon, however, continues to find ways to break his prison and attempt to take over Earth.

Heroes

 * Trigon's forces find their way to Earth and end up attacking the Tomorrow District. He even takes control of Raven to destroy the city and captures the other Titan members Cyborg, Starfire, Nightwing, and Donna Troy while corrupting them. When the players free the possessed Titans, Trigon's hold on Raven gets stronger causing the players and the Titans to split up to find Raven. With help from Zatanna, the players end up heading into the portal to Raven's soul self where Trigon uses Raven's possessed spirit to attack the players. After helping Raven fight the last Possessed Raven Spirit, Trigon's evil escapes to Earth.
 * While being brought to Earth by Brother Blood, Trigon sends his demon minions to corrupt the citizens based on some of the Seven Deadly Sins. Brother Blood's plans to bring Trigon to Earth were thwarted by the Sentinels of Magic.

Trivia

 * Trigon first appeared in New Teen Titans #4 (February 1981).