The Unaware Atelier Master

One day, you, a kind-hearted boy, is suddenly kicked out of the Hero's Party for being "useless." You find that your aptitude for weapons, magic, and all other combat-related skills is the lowest rank, so you take odd-jobs repairing the castle walls and digging for minerals, where your exceptional abilities are immediately revealed. You prove to be skillful in cooking, building, mining, crafting magical tools—in fact, your aptitude for every skill unrelated to combat had an SSS-ranking! However, you seem completely unaware to your talent and ends up saving people, the town, and even the country through your unaware actions!?