In the Card Master era, otherworldly projections invade reality, and supernatural powers take the form of cards. Anyone who obtains a card can gain power.
Chu Ming transmigrates into this world and obtains the Book of Ages, which can rewrite the history of other worlds. From then on, he sets out to save a world on the verge of being swallowed by darkness, leaving behind legend after legend in other realms and forging Mythic Cards of his own.
[Troll Slaughterhouse] [Wild Hunt Knight] Return to an age overrun by dark creatures and set all things right.
[Primordial Blood Pool] [Vampire Progenitor] Master the power of blood in a dark form and fuse the blood of a hundred races.
[Origin Divinity] [Forbidden Wizard] Draw the power of negation from the source and seal away the darkness.
As each legend is etched into history, Chu Ming looks back in a sudden moment of realization and finds that he has become a myth.
(An otherworldly savior story, dungeon-focused, with a decisive protagonist who kills without hesitation.)