Adam finds himself transported to the Cretaceous period, filled with dinosaurs, and becomes a participant in a game of civilization creation. Just as he plans to lead the primitive people generated by the system in a realistic wilderness survival, the recruitment of a girl claiming to be Jeanne d’Arc through the Great Person system and a large clump of extraterrestrial fungus falling from the sky leads Adam to an epiphany. What, is this place actually Type-Moon?!

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In the 25th century BC, the oldest tribe known for taming dinosaurs helps Uruk combat the returning Tiamat. In the 11th century BC, they once again stand side by side with gods from outer space, defeating the avatars of giants on the lands of Egypt and Greece.

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In the 15th century AD, they pioneer sea routes to America and Asia, confront the culprits behind ecological extinction, and unify the Far Eastern island split into “eight million” parts. They form an alliance with the immortal Jade Dragon. In the 18th century, they face the seven Beasts symbolizing the apocalypse and eight UO from an extermination star, disregarding Earth’s will.

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Starting with the black-clad Jeanne d’Arc, countless heroic spirits from the future and even other histories are summoned to assist. By the time Adam crafts mechas for the apocalypse, he looks at the members of Chaldea in front of him and falls into deep thought. Oh no, could this be an interlude of anomalous tales?