Can’t remember the name

I think it was a webtoon all I remember is the mc was the youngest born in a family of swordsmen who hate magic or they think it’s weak or something but he has really strong magic and he trains it secretly so his family never finds out and at one point he finds a secret room in one of his family’s mansions and there’s a guy trapped inside that served his ancestor who had the same kind of magic as him. Thanks in advance for any help.