Anubis' Age Cocoon

Wisps of negative energy flow from your pores, nose and mouth and towards a targetted area, the energy will solidify in a 20 foot sphere around that area, encasing any creature within that radius inside, trapping it. In order to escape, it can use an action to make a strength saving throw and attempt to force their way outside of the cocoon, if they succeed, they are free once more.

Whilst a creature is trapped inside of the cocoon, they begin aging rapidly as their bodies become wrinkled and weak, for every round started inside the cocoon, their strength, dexterity and constitution scores all drop by 1 point and they take 3d10 necrotic damage. 

Once, or if, a creature manages to escape your cocoon, their stats will slowly return to normal over the same amount of turns they spent suffering within the cocoon, example being if they spent 6 rounds in the cocoon having their scores lowered by a total of 6, it will take 6 rounds outside of the cocoon to repair them. If any of their scores reach 0 whilst within the cocoon, however, they will die.

At higher levels: for every level above 4th the spell is cast, the damage will increase by 1d10, every level above 7th the spell is cast, their ability scores drop by 1 more.