Babel was the Centaurus saint in XX Century.
Babel was sent to kill Seiya in the anime and the manga, because he disrespect the Sanctuary law. But, in the manga, Misty attacks the Mount Fuji and kill Ikki (another sinner) and Babel, Asterion, Mousses and Marin was sent with him; but Mu teleports the black saints and Seiya, Shiryu, Hyoga and Shun and Marin guides the 3 comrades to kill the wrong victim; Babel kill the Black Cygnus, Asterion kill Black Andromeda and Mousses with Black Draco, and these black saints was confused with Hyoga, Shun and Shiryu; Marin simulates kill Seiya, and the 4 corpses are buried in the beach; but Misty asks to Marin, Mousses, Babel and Asterion leave the place.
Babel came back to the back, where Seiyas already left, but Seiya left a card to notices Misty death. Babel finds Misty corpse and the card, and Hyoga arrives there because felt Seiya's Cosmo in a fight, but he disappeared (can he is dead?), and Babel thinks he has killedHyoga, but Hyoga doesn't recognize Babel.
Hyoga says Babel can't differentiate gold of fools gold, and Babel makes flames, and they are not fakes. Hyoga defeats Babel and leaves a Cygnus card in his corpse, and continues searching for Seiya, leaving the local.
In the anime, Babel appears after Asterion, Marin, Misty and Mousses, and attacks the Graad Coliseum, and almost defeat Hyoga, Shun, Seiya, Ikki and Shiryu, but the steal saints help Hyoga to kill him, and before dying, Babel recognizes Saori as true Athena, and she forgives him.
In Hades chapter, he tries stops Hyoga with Misty and Mousses, untilhe doesn't disturb Shion's action in the Sanctuary.