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Overview 1
In order to prevent the loss of the valuable human resource known as the "Heroes," an update to the Hero System has been scheduled.
It will allow the Heroes to employ the fairies that have been sealed in the Old Era.

All that exist in this world is being stored in the form of conceptual records within the Shinju-sama. These records can be accessed and extracted to manifest their powers within one's own body - this is essentially how fairies were used in the final war of the Old Era. The beings such utilized were
-"Ichimokuren," who drastically increases the subject's speed
-"Yukijorou," who bestows the ability to use ice-based attacks upon the subject
-"Wanyuudou," whose large wheel can be used both as a weapon and a means of transportation
-The "Shichinin Misaki," who split the subject into seven separate bodies, making it immortal unless all seven are destroyed simultaneously
-"Yoshitsune," who grants the ability to use various sword techniques and increases the subject's agility considerably
-"Shuten-Douji," who imbues the body with tremendous strength in battle
-"Daitengu," a being with enormous wings that brings destruction upon the land

The fairies granted the Heroes immense powers to the benefit of mankind. However, it must be remembered that the powers commanded by the fairies are by nature beyond human understanding. The following paragraph will provide further insight into this issue based on the research undertaken by the Christian Era Hero Iyojima Anzu-sama.

Overview 2
Two fairies are to be employed this time.
The Crow Tengu shall be given to the Nogi family, as it befits their ancestor.

These beings show qualities of evil spirits. The practice of summoning fairies and letting these non-human creatures possess a human's body is an art closely related to necromancy. The concepts of phenomena such as communication with the dead or spirit possession have been part of human culture since ancient times. Shamans, itako, yuka, sayaniwa - they all allowed non-human beings to enter their own bodies; there have even been instances of humans being possessed by dog or fox spirits. However, such practices are inherently dangerous: Possessions by dog and fox spirits go hand in hand with curses. The boundary between human and non-human can become blurred at times, and the use of a Trump Card can be understood as dipping a part of one's body into what lies beyond this boundary.

It has become apparent that repeated summoning of fairies by this method has a major drawback, namely that it causes miasma to build up within the subject's body, which negatively affects their psyche. The symptoms include anxiety, distrustfulness, increased aggression, loss of self-control, pessimism and a tendency towards fatalistic thinking, among others. In short, the subject becomes mentally unstable and displays a tendency towards dangerous behavior.
In light of this, fairies shall not enter the human body under the new system.

Overview 3
The fairies are to be employed by manifesting them outside of the body.
As fairies are capable of using their powers to repel enemy attacks, they are regarded an effective means to prevent losses among the Heroes, who are already few in number. Another advantage of this method is that in the unlikely event the need to recruit new Heroes should arise, there will be no need to have them undergo intensive training before their deployment in battle. However, since the new system will consume tremendous amounts of energy from the Shinju-sama, the number of Heroes will be limited to five to six people.

The new Trump Card, Mankai, does not merely improve defensive capabilities, but also increases offensive power, which will allow the Heroes to overcome any difficult situation that may arise in combat. Mankai is a grand technique which releases the energy that is being accumulated while the Heroes use their powers, pushing their capabilities to the limit for a certain period of time.
Still, such great power comes at an equally great price for the Heroes.
This will be elaborated upon in the following paragraphs.