The Pure Hearts are powerful artifacts created by the Tribe of Ancients in Super Paper Mario. All eight Pure Hearts are components of the Purity Heart, and they were created by the Ancients using various different types and forces of love, which was believed to be the only force powerful enough to save all worlds from destruction.
The Pure Hearts were created as part of the prophecies detailed in the Light Prognosticus, which state that four Heroes of Light must gather all eight of them in order to counteract the Chaos Heart and defeat the one who wields it. When placed in a Heart Pillar, each Pure Heart leads to a dimension where the next one is located, through a series of doors at the top of Flipside Tower.
The first Pure Heart is held by a descendant of the Ancients named Merlon, who gives it to Mario, the first of the four heroes, with the task of traveling through dimensions in order to gather the other seven and stop Count Bleck from destroying all worlds using The Void. During his journey, Mario eventually comes to reunite with Princess Peach, Bowser, and Luigi, all of whom are proven to be the remaining three Heroes of Light, and together, the four of them manage to collect all eight Pure Hearts and travel to Castle Bleck to battle against Count Bleck, the holder of the Chaos Heart.
The eight Pure Hearts, as well as their locations and the sources of love they correspond to, are listed below.
Despite the immense power of the Pure Hearts, they are not indestructible, as was shown when one of them was consumed by The Void along with the rest of Sammer's Kingdom. This led to the Pure Heart losing its power and being turned to stone until it was revitalized by Queen Jaydes of The Underwhere, using her power over life and death. Also, the power of the Pure Hearts is depleted after they are used to break through the Chaos Heart's protection over Count Bleck; this allows Dimentio, under the guidance of the Dark Prognosticus, to usurp control of the Chaos Heart unopposed following Bleck's defeat, fusing together it, himself, and Luigi to create an invincible monster known as Super Dimentio.
However, the loyalty of Bleck's minions, Nastasia, O'Chunks, and Mimi, serves as powerful enough to return power to the Pure Hearts, which subsequently weakens Super Dimentio's power and allows the Heroes of Light to eventually defeat him. However, Dimentio uses the last of his power to sustain the Chaos Heart long enough to ensure the destruction of every world. In their final moments, Count Bleck and Tippi - now revealed to be long-lost lovers Lord Blumiere and Lady Timpani - reaffirm their love for each other, sacrificing themselves in order to save all worlds; their vows manage to unite the Pure Hearts into the Purity Heart, destroying the Chaos Heart and reversing the prophecy of destruction.
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