The Mammoth Gang
A Gang following their leader, the Titan's old enemy: Mammoth. They are the main villains for Season 1.
- Mammoth - the leader of the gang.
- Wolly - second in command
- Mammoth Minons - the Goons.
Red X/Jason Todd
An enemy of the Titans that fell to his death. Nightwing and the old team blaim his death on themselves. He is the main enemy of the Original Titans in the Flashback episodes.
An enemy of the Teen Titans Beyond. He is hired by the Mammoth Gang to duplicate Beast Boy's powers and give them to the gang. But an accident will change it all...
The League of Shadows
Led by the once great Ra's al Ghul, an enemy of another hero, the League of Shadows is now working with the remains of H.I.V.E. to create the greatest group of supervillians ever. They are one of the main villains in Season 2.