Magicians

Mages
Mages are people capable of providing magic power to spirits to perform techniques called Magic spells. Mages can't use spells if there is no spirit to help make it happen. Mages are chosen by spirits for what attributes they can use. Which the four attributes are Fire, Water, Wind, and Earth. It is not known if when the person is born is when the spirits choose or if it's later in life when they are a child. Normally a mage can only use one attribute but in rare cases, people can have more than one. A Single Magician is a mage that can only utilize one of the four elements. Though in the second episode it is shown that there are 3 types of magicians. The most common unique case is Dual Magicians, They can use two of the attributes. A rare of these unique cases are the Triple Magicians, Like there name, they use 3 of the attributes. The last and rarest of rare cases are the Quad Magicians, which are capable of using all the attributes. It is shown in the serious during magic training that you incantations as a beginner mage and also you need to imagine how the spells work before using them. Meaning that creativity and imagination are key in magic spells. It also is shown that mages can use magic to enhance their own bodies.

Types of Magicians
Single Magician - A Single Magician is a mage who can only use spirits and spells of a single attribute. This is the common case for most mages in this world.

Dual Magician - Dual magicians are uncommon and are capable of using magic spells from two elements. The only person is shown in the show to be a dual magician is Muller. Who could use the attributes of fire and earth.

Triple Magician - Triple Magicians are magicians able to utilize three attributes. These are rare and aren't seen much in this world. With only one case of a triple magician being Lemia.

Quad Magician - Quad magicians are extremely rare. Being able to use all of the attributes giving them great versatility and power. There is only one case of a Quad Magician in the story for right now and it is Rin Azuma.

Unique Magicians/Sorcerer's- Sorcerer's are also classified as Unique Magicians due to utilizing abilities that are outside of the norm, such as Light, Darkness, and Space-Time. Taichi who is a Summoner falls into this category.