Craters appear frequently, giant beasts run rampant, and Earth enters a catastrophic era. Humanity from the cosmos introduces card technology civilization, and cards save the world, leading to the establishment of the Earth Federation. The Green Giant series of cards can enhance human physical strength, codenamed "莽" (Mǎng). In the Qi Bullet series of cards, the strongest card can even release a Spirit Bomb. The Blue-Eyes White Dragon series of pet cards allows for pet cultivation, ultimately evolving into a dragon-kun. Gale Card + Low-level Demon Heart Card = Combination Skill "Gale Demon Heart"; Gale Demon Heart + Ghost Servant Card = Combination Skill "Ghost Servant · Jil".