Foal Titans
From Equestripedia, the Archives of Equestria!
The Foal Titans were a famous superhero team. Shining Armor was a huge fan of them and had their poster on his wall.
Members
Behind the scenes
The Titans are a reference to the Teen Titans of DC comics fame. In this universe however, they appear to be published by IDW, who also apparently publish Harley Quinn, Death of the Endless and...Deadpool of all things.