The Legendaries

It is set in a world called Alysia. The Legendaries are five heroes who, in an attempt to stop an evil sorcerer named Darkhell from using the Stone of Jovénia, one of six magical stones used to create the world of Alysia, were unable to keep it from shattering, causing everyone in the entire world, themselves included, to revert to childhood. Blamed by the people of Alysia for the "Jovénia Incident", the Legendaries split up, only to be reunited by their leader Danael for another adventure to undo the spell and restore their adulthood.