The Return of the Dark Sun is the approach of a zero-point energy field towards Earth.
It is the Second Trial set for humankind by the Super-Ancient Beings.
Early History Edit
At a currently unknown point in Earth's history, a race of Super-Ancient Beings discovered the Dark Sun and through their research learned that it comes closer to the central Sun every few million years, but its' deadly radiation is blocked from hitting Earth by Jupiter and Saturn. However, they predicted that on rare occasions the gaseous planets would not protect Earth, and that any life on the planet at that stage would be wiped out.
The Super-Ancients then set about constructing a machine, comprised of six vertices containing an inverted pyramid, which would work in conjunction with six oblong diamonds they also manufactured, referred to as Pillars. Through these, on any day that the Dark Star breached the safe distance between itself and Earth, each inverted pyramid would fire a concentrated laser at the Earth's very core, which would then send out a sonic vibration that was powerful enough to keep the Dark Sun at its safe distance.
Though they were able to prevent the Dark Star from approaching in their time, the Super-Ancient Beings realised that even after they were gone from the Earth (by extinction, or otherwise departing the planet), there may yet be intelligent life, and so made the prevention of the Dark Star the second of five trials which would allow them to determine if a new sentient species did arise and were worthy of existing.
To this end, they constructed tools that would help to cleanse the Pillars, reveal the locations of each Vertex, the dates each Pillar had to be laid, view the Dark Star and reveal the incantation that would activate the Machine.
After the Super-Ancients were gone, the Dark Star continued to make the odd breach into the solar system, though the planets were largely unaffected by virtue of the gas planets' orbits. However, on one occasion, the Dark Sun's energy destroyed a small planet between Mars and Jupiter, causing an asteroid belt to form.
At some point during the rise of human culture, the Super-Ancient Beings returned and provided a collective group with knowledge of the Dark Star, as well as the tools that would allow them to find the Vertices of the Machine, as well as the six Pillars. Eventually these Machine components came to be kept in Egypt under the Pharoh Khufu's keep (himself apparently being a King of one of the Four Legendary Kingdoms). However, the priest Thuthmosis stole the Pillars and the Sacred Stones, unwittingly putting the Earth at greater risk of being destroyed by the Dark Sun as they were scattered around the world.
Before The Six Sacred Stones Edit
After The Five Greatest WarriorsEdit
Years later, Cardinal Ricardo Mendoza explained to Jack how the return of the Dark Sun and its repelling was the second of five tasks set by the super-ancient beings to test life on Earth. (The Four Legendary Kingdoms)