Ancient Bloodline Legacy Challenge (Realm of Magic)

I used the Potion of Rejuvenation to reset their current age. The Potion of Immortality just stops elders dieing from old age. Mind you, using a potion to stop aging is completely optional and you can let your spellcasters age normally if you want to feel normal aging progression. After some time, you will find that your original Sim will not have much to do especially if you are using Potion of Plentiful Needs to give your sim very little downtime.