Even in magical worlds, magic won’t always be the answer to problems. It is not unreasonable to expect that the use of magic will always have a price to pay. In my fictional world, this price is the more magic you use, the more you will drain yourself of energy.
All magical beings in my world have to top up their energy supplies but all have got used to the idea of using machines and other methods to save their natural resources as much as possible.
So how do your magical characters top up their powers? What powers are permanent? Which have to be renewed and how is that done? Can your characters steal powers from one another and, if so, what are the consequences of this?