The dragon gems are known artifacts that can make the Legacy of the Dragons grant anyone's wish, all the infinite powers of the elements inside the precious minerals need to be mixed close so the dragons can be summoned. The Evil King Koopa known as Bowser wanted the wish to rule the entire world in the year 2013, but he was defeated and stopped by Lucario, Pharaoh Man, Mondo Owada and The Rapa-Nui Friends, ruining his plans, however, that's another story.
-Introduction Prologue · A Grim Origin of a Reaper Soul-
One mysterious entity managed to reunite the dragon gems into one faraway place, and placed the objects into the pillars. A huge beam blasted from the gems, summoning the elemental dragons: Seiryuu the Water Dragon, Exfeuertod the Fire Dragon, Quetzalcoatl the Wind Dragon, Zanduluho the Earth Dragon, Lizarsteel the Metal Dragon, Tarkhazarp the Thunder Dragon and Nobodfrost the Ice Dragon. Normally Exfeuertod hated humans and would attack the invoker before his brothers will calm him; however, this case the entity wasn't a human. "Tell me your wish, mortal, and we could grant it". Said the water eastern dragon with his ominous voice. "Grant me the wish to make me return to my time, and the death of my parents to never happen." The words from the entity begged for the mystical creatures, in which they negated with their heads. "That is impossible, our power is not beyond to touch the alternate universes, and we cannot coequal contact our many dimensional counterparts." The wise words from the frozen but noble dragon made the being change its commanding wishing words. "…then… make my parents that never meted each other in this timeline, to meet right now and accept me as the child I was once." "Not coequal that wish is possible, we cannot interfere or modify ye love from another for its own ambitions." The mysterious being went into an angered silence and then recovered its patience, by requesting for a simpler wish. "Then how about… bringing me the power to kill anything, gain power from the souls collected to either my outside steel or my inside flesh. To let me command other beings that will have the same proprieties of my unlimited power but the limitation of having it below mine. When there is a natural disease, suicide, accident, murder or the end of the age, I and my comrades can be there, to pick their lives when the mortal time has come. Let me be Death." The dragons looked each other, they knew that this was an acceptable wish, but, if they fulfill it, there can be consequences, but they had no option other than continue and grant the wish. "Your wish has been granted." They brought the power for the entity, turning it into the Grim Reaper. When the desire has been fulfilled, the dragons returned to their Legacy Room by disappearing from the mortal world, and so the gems floated away right to their temples around the world, separating again until another call from anyone who reunited the precious minerals could awake them again to grant its wish. The strange entity smiled with its new powers, and leaved the place.