[Unified Earth] The world has been unified into 'Unified Earth,' and the concepts of nations and governments have vanished. The sole ruler of the world is Kim Woojin, the only EX-rank Gift user, and all humans are his subjects and tools. No one can rebel against or oppose Kim Woojin; his commands and authority are absolute.

A society ruled by strict Gift-based hierarchy, meritocracy, and the law of the jungle. Those with value gain power and honor, but those deemed worthless are discarded at any time.

[Sky Island / Lower World] A massive floating city, 'Sky Island,' exists in the skies above Seoul. Sky Island is the center of power where the world's top Gift users gather. Under Kim Woojin, various departments collaborate to operate Unified Earth. Each department has a different specialty, and while their authority and influence vary, they respect each other's expertise and necessity.

The ground below Sky Island is called the 'Lower World.' Non-awakened people without Gifts and a small number of Gift users who failed to enter Sky Island live there. While schools and living facilities exist, the overall standard is far lower than Sky Island. Even a talent recognized in the Lower World is considered common and ordinary on Sky Island.

[Gifts] Only a very small number of people awaken a single Gift. Ranks: F → D → C → B → A → S → EX Categories: Broadly divided into Combat and Non-combat. Specifically categorized into Attack, Defense, Support, Healing, Mental, Summoning, and Special types.

Gift users are subjects of management by Sky Island.

Since only one EX-rank can exist in the world, no one other than Kim Woojin will ever appear.

S-rank Gift users are rare even on a global scale, with barely one appearing per year.

Gift rank is the absolute measure of power, class, and position.

Gift rank measures an individual's talent and output; higher ranks possess greater power, longer lifespans, and immense authority. Gift rank is the standard for class, power, and social status. Rank and position take precedence over age and origin; those who awaken high-rank Gifts at a young age are treated with corresponding respect.

The rarity and utility of a Gift are also considered important. Even within the same rank, rare Gifts are recognized with higher value, and even low-rank Gifts that are difficult to replace are treated as essential personnel. Rarity and utility vary by Gift type.

After awakening, a Gift can be strengthened or its application improved through training and effort, but it is rare for the rank itself to rise.

Even non-combat Gifts are respected and protected if they are rare and hard to replace. Acts where a low-rank combat user ignores, oppresses, or demands combat from a higher-rank non-combat user are considered despicable and undignified.

Since Gift rank is absolute authority, lower-rank Gift users must obey higher-rank users.

[Currency] The currency unit is 'Credit (CR).' The value of a Credit is equivalent to the currency of the pre-Unified Earth era, where 1000 CR equals 1000 Won.

[Selection Day] Held once a year at the end of December, 'Selection Day' is when talents are scouted for Sky Island. Anyone who awakens a Gift for the first time that year, regardless of age, is forcibly brought to Sky Island for selection. Their Gift rank, name, and category are measured, and they demonstrate their abilities to be scouted by a Sky Island department or discarded if deemed useless.