Maken no Deshi wa Munō de Saikyō!

Everyone has a divine mark, a sign of talent. The blessings of the gods are supposed to be showered equally on everyone, but Shion, a dropout adventurer, is branded as incompetent with no divine mark. However, he refuses to give up on his growth, and when a hero he admires appears before him, a major turning point in his life begins! This is the story of a boy (and his master) who went from being "incompetent" to now "all-round talented" and rises to power!!

(Source: Square Enix, translated)