Children of Mirra

Sein, a child of unknown origin, embarks on a lone journey throughout the mystical and dangerous world of Mirra. Sein's master, the Great Sage, was forced to part ways with him in order to do battle with a fearsome foe. On his own, Sein slowly discovers his true self, meets friends along the way, and experiences things he couldn't while under the Great Sage's watchful protection. Upon discovering more about himself, he learns he harbors a power strong enough to become the world's greatest hero... or its greatest nightmare! Source: Webtoon