Divine Summoning (神威召喚 Shin'i Shōkan , God's Power Summoning) or simply Summoning (召喚 Shōkan ), is the term used to refer to ceremonies requesting the advent of the true Gods of the Crimson Realm. It is not known whether this ceremony is a type of Unrestricted Spell or not.
Background and Usage
Divine Summoning ceremonies can be generalized as having two steps: "Directing God's will towards the one who seeks their power" and "making a sacrifice as compensation for gaining God's consent". When a God's power is summoned using this ceremony, they are able to wield greater power than usual that is aligned with their authorities.
The Divine Summoning concerns the summoner paying their compensation or sacrificing something to call out the Gods (or activate his powers). The Gods have their own way of summoning; Alastor uses nearby Crimson Denizens (whether their agreement or not) as the sacrifice, the Snake of the Festival and Shaher uses their Servants.
Summoning in the birth of Flame Haze
The concept of Divine Summoning is applied in the ceremony to give birth to a Flame Haze. Though Divine Summoning ceremonies were for summoning their respective Gods, Crimson Lords of ancient times feared the Great Calamity which would occur from the rampage of Crimson Denizens in this world and adjusted the ceremonies so that they would be usable with them. The human, likely to have a grudge against Denizens, would conduct the ceremony, offering their entire existence, which is their Vessel Known as Destiny, and the Crimson Lord selects the resulting vacuum as their Vessel, summoning and transferring themselves inside the Vessel. This results in the birth of a Flame Haze. This ceremony is not to call forth the authorities of God, but merely an operation in which compensation is made in order to transfer into this world.
- see full article: Resummoning
Another example of an application of Divine Summoning was "Abyssal Ring" Asiz's Unrestricted Spell Resummoning. In this case Asiz, who was both the summoner and the one to be summoned, secured the Power of Existence needed to manifest beforehand, then offered his connection to the Crimson Realm in order to summon and transfer himself outside his Vessel, "Weaver of Coffins" Tis, releasing himself from the body bounded to this world and allowing him to manifest. If he simply wanted to manifest in this world as a Crimson Denizen, there would be no need to resummon himself, but Asiz chose to pay compensation and transfer outside his Vessel while preserving the use of his power, Pure Coffin. He had resummoned himself in order to not destroy his Vessel, the corpse of Tis.
List of Divine Summoning
Below is the list of Divine Summoning revealed in the story so far.
Tenpa Jōsai (天破壌砕 Heaven Destruction Earth Break ) : The most renowned Divine Summoning in the series which is the ceremony to summon Alastor, the true Crimson God who have the authorities over "Judgement" and "Conviction". This ceremony was first performed by Mathilde Saint-Omer as the mean to stop Asiz's Grand Scheme during the Great War. In that time, Jarri was the sacrifice for this Divine Summoning against his will. Only Alastor's ceremony seems to have a chant during summoning.
Saiki Reisō (祭基礼創 Ritual-grounding, Ceremony-creation ) : The ceremony to summon the Snake of the Festival's authentic powers over "Creation" and "Settlement" to create thing. This ceremony is performed during the final phase of creating Xanadu, the Denizen Paradise. The compensation of the summoning is the Priestess of the Trinity, Hecate.
In the Snake of the Festival's case, it's not called "Divine Summoning/God's Power Summoning" but rather "God's Power Recalling" (神威召還 Shin'i Shōkan ) which has the same pronunciation in Japanese. It is not Summoning but Recalling likely because Snake of the Festival is already manifested when Saiki Reisō is to be carried out.
Shōhi Ginsei (嘯飛吟声 Scattering Roar, Chanting Voice ) : The distinctive ceremony performed more than other Divine Summoning. The ceremony is to summon Shaher's voice which is sent to every single person involving the Crimson Realm; Flame Haze and Denizens alike. This voice cannot be blocked meaning everyone will know about the news Shaher announced. The news she had announced includes How to crosses the Rift, existence of the Treasure Tool, Spell to take human shape and Flame Haze's creation. Shaher will be summoned through sacrifice of her designated servants who roam the world searching the new thing which has to be informed to everyone.
In Shaher's case, it's not called "Divine Summoning" but rather "Divine Will Recalling" (神意召還 Shin'i Shōkan ) which has the same pronunciation in Japanese. Instead of God's Power Summoning it is Divine Will Recalling likely because Shaher has no physical body to be wielded.
- The ceremony's name is the usage of the God's true names: Alastor's "Ten"pa "Jō"sai from his name, Tenjō no Gōka (Flame of Heaven and Earth); Snake of the Festival's "Sai"ki "Rei"sō from his name, Sairei no Hebi; Shaher's "Shō"hi "Gin"sei from her name, Kaku no Shōgin.
- Shakugan no Shana Light Novel Volume 10 Chapter 04 page 175