Ancient Rage

Calling upon your ancestors, you let a ray of pure white light burst from your hands, each creature in a 60 foot radius must succeed on a Dexterity saving throw on a failed save, they take 4 d10 radiant damage and 4d10 force damage, or half as much on successful one, or instead of a blast, you can choose to empower yourself with the ancient rage, while empowered, you have advantage on all attacks and do more damage the older the weapon is, P.S.: if used on a creature bigger than you, the creature gets weakened down to 3 hitpoints and has to beg for mercy