Ok here my idea of a power system
This is a world of magic and sword like for example if you used sword or fist your are a aura user and if you used magic you a magician for you to become one you have to go to a magic hall and get chosen by a spell book
First one is every being on the planet can use the power of a Spirit/dijin. They are basically god who grants power to their user
They are different rank of dijin u can form contracts with like example
Low rank
Medium rank
High rank
King rank
Basically, the dijin are elemental so they grant elements to their user
Fire
Water
Earth
Wind
Lightning
Dark
Light
Life
Chaos
You can be in contacts with only three dijin at a time but it possible to contract with all the elemental dijin but it come with a price.
Dijin have different rank it have a king of all elemental but it hard to form a contract with a king because it have they own ego and they have to choose you it no way for you to summon them.
In this world you can also become a beast tamer it a lot of beast u can tame like dragon but beast like dragon have high intelligence so it not common to be able to tamed them but it can be done