Hidden Deed Illustrated Book: Collect All 8 Serial Spirits?

Supernatural events known as "spiritual tides" broke out all over the world at the same time. Cracks appeared in the space, and ancient alien spirits from another dimension - the "other shore" poured into the world. There are many types of supernatural spirits, some are docile, some are ferocious, and some have the power to destroy the world. Spirit envoys gain power beyond ordinary people through contracts and become the core combat force in the new world order. The mysterious illustrated book in which the male protagonist awakens has an unknown origin. It far exceeds the contract ability of ordinary spiritual envoys and is a mysterious existence that transcends the illustrated book. Each of the foreign spirits in the Hidden Contract Illustrated Book has "authority level" power, and is engraved with the same mysterious mark "Hidden Mark" on its body. The Pokédex cannot track them, it can only sense them.