Saya Otonashi is a seemingly ordinary girl living a mundane life with her adoptive family in Okinawa City. In fact, her only peculiarities are suffering from anemia and being unable to remember any of her life beyond the previous year. However, Saya's forgotten past quickly comes back to haunt her—one night, she is attacked at school by a creature that feeds on human blood. Just when all hope seems lost, a mysterious man named Haji appears and fends off the creature temporarily. But when her rescuer forces her to drink his blood, Saya suddenly enters a trance and slays the monster with ease, using her own blood as a catalyst. Saya then learns of an organization named Red Shield, founded for the sole purpose of defeating the hellish beasts. Now Saya and Haji must work together with Red Shield to fight these fearsome monsters and unlock the secrets to the girl's past.

Unbeknownst to most humans, a bizarre tournament is held to decide the next ruler of the Heavenly World. In this tournament, 100 Heavenly Beings known as the "God Candidates" are required to search among the middle school students on Earth, and transfer their powers to a student of their choice. The chosen ones will then battle each other, representing their God Candidates. The victor of this tournament will be awarded the "Blank Talent"—allowing them to choose any one unique ability they so desire—while the God Candidate they represent will obtain the position of "God" and become the king of the Heavenly World. Participating in this grand tournament is Kousuke Ueki, a middle school student who is given the power to turn trash into trees by his homeroom teacher, Kobayashi. Despite the concerns of his classmate, Ai Mori, Ueki embarks on a journey to pursue his own sense of justice after witnessing the people around him misusing their powers for selfish purposes. But as he encounters talented power users such as Seiichirou Sano, Rinko Jerrard, Robert Haydn, and Hideyoshi Soya, he realizes that achieving his goal might be harder than it seems. [Written by MAL Rewrite]

Legend says that the enigmatic Millennium Puzzle will grant one wish to whoever deciphers its ancient secrets. Upon solving it, high school student Yuugi Mutou unleashes "another Yuugi," a peculiar presence contained inside. Now, whenever he is faced with a dilemma, this mysterious alter ego makes an appearance and aids him in his troubles. Wishing to unravel the mystery behind this strange spirit, Yuugi and his companions find themselves competing with several opponents in "Duel Monsters," a challenging card game used by people seeking to steal the Millennium Puzzle in a desperate attempt to harness the great power within. As the questions pile on, it is not long before they figure out that there is more than pride on the line in these duels. [Written by MAL Rewrite]

Continuing their journey from Record Country (the place that held the book of memories), Syaoran and company land into Tokyo Country, a blood-filled country under war from opposing factions for natural resources and survival. While reluctantly involved in the race to live, the group faces their own problems as certain revelations are made, changing their journey forever. A shocking betrayal and a battle that risks all of their lives. After this revelation, they will never be the same again.