Aging

A sickly gray bolt of energy shoots out from your outstretched hand towards a creature within range. A creature that doesn’t age or is immortal is immune to this spell. Make a ranged spell attack. On a hit, the target must make a Constitution saving throw. The target takes 6d10 necrotic damage and instantly ages that many years on a failed saving throw, or half as much damage and years on a successful one. In either case, the creature is also knocked unconscious for 1 minute. If the target dies from this damage, it is considered to have died of old age and can only be brought back through a wish.

The aging is permanent unless reversed with a greater restoration spell. The aging has no game affects unless the DM determines that the target has been pushed into extreme old age. In that case, the creature takes one level of exhaustion, which cannot be removed unless the spell is reversed.