Celestial Spirit Magic

Celestial Spirit Magic (星霊魔法 Seirei Mahō) is a Holder Magic used by Celestial Spirit Mages that involves the summoning of Celestial Spirits.

Description
Celestial Spirit Magic is a Magic in which the user summons Celestial Spirits by opening their gates through the use of Celestial Spirit Gate Keys. These Keys are separated into two classes: the more common Silver Keys and the rarer Gold Keys. Keys for Celestial Spirits are counted in Units (collectively without regard of Gold or Silver), and a Celestial Spirit Mage is noted by how many Units they have obtained.

Contracts and Rules
When a Celestial Spirit Mage receives a Key and opens its Celestial Gate for the first time, they have to set up a contract with the respective Spirit. This contract consists of asking the Spirit which days it can be summoned by its contracter. This simple agreement, much to the surprise of Natsu Dragneel and Happy, leads to a dedicated and serious bond between the Spirit and summoner. However, under certain circumstances, i.e. during battle, and a Spirit is summoned for the first time, the making of a contract may be suspended on a later date. Contracts can be broken if the Mage gets arrested, releases the Spirit by himself/herself, or dies. When a Celestial Spirit Mage summons a Spirit, it appears directly next to them, as that's where the gates to the Spirit world had been opened. It's impossible to summon spirits elsewhere.

The Spirits must also abide by certain rules enforced by the Celestial Spirit King. The only rule that has been introduced in Fairy Tail so far is that a Spirit may not directly or indirectly kill its summoner under any circumstances. When the Gates are closed, it is required from both the summoner and the Spirit to agree upon the gate's closure. However, Spirits can also be "forced closed" in battle, which means they can be forced back into the Celestial World by the summoner's will, though not every Celestial Spirit Mage is capable of doing such.

Celestial Spirits also have different categories of sorts that fall under the basic summoning conditions from their owner. For example, Loke summons himself most of the time without Lucy Heartfilia doing so herself; Virgo has also summoned herself various times, as have Gemini,Taurus and Horologium. Also, if the trust between the Celestial Spirit and the owner is not an issue, contracts can be temporarily dissolved. It also seems that if the Celestial Spirit is strong enough, they can employ their own Magic to stay in the Human World, when/if the contract is not in action. The strength of the Celestial Spirits is affected by the Magical strength of their summoner, as Lucy once said that her spirits could become even stronger than Natsu if she trained more.

Spells

 * Summon Celestial Spirit: A Celestial Spirit Mage is able to summon Celestial Spirits from another dimension by using the Keys of the Gates. Celestial Spirits can aid the Mages in battle, do chores for them, or even just play with them.


 * Gold Keys


 * Force Gate Closure: Closing the gates requires a mutual agreement from both the summoner and the spirit. However, some Celestial Spirit Mages have demonstrated the ability to force the gates to close in battle, compelling the Spirits to return back to the Celestial Spirit World.


 * Multiple Summons: Summoning more than one Celestial Spirit uses up a lot of the summoner's Magic ability which may even lead to their death. However, some Celestial Spirit Mages have shown the unique capability to summon multiple spirits at the same time.
 * Combination Attacks: If one is capable of using multiple summons, it gives them greater flexibility as he/she is able to combine the attacks of their Spirits to form new and more powerful ones, in a similar manner to Unison Raid. They can also use their own magic in combination with another spirit to increase the power of an attack.