As the One Being created planets that would one day allow life to grow and thrive upon it, the One Being also left behind a fragment of his power, enough to sustain the planet. While minute in comparison to his own omnipotence, the power he left behind remained sufficiently immense to gain its own consciousness, in the form of seven pure entities of energy.
These seven were beings of pure cosmic essence, void of gender and immune to the ravages of time and space; and they named themselves what could be roughly understood as: "the First Children".
While the First Children were created from an energy that was to sustain the planet, it has been argued throughout history that it was in becoming mortal to understand humanity that the First Children would protect and sustain the Earth.
At the planet's beginning, the Earth was nothing more than molten rock and ash. Yet as time progressed, the atmosphere began to form and rain would eventually fall to fill the caverns hewn out by the Earth's formation. Oceans were created, and gradually, life emerged. As time continued onwards, humanity was born.
Throughout all this time, the First Children watched as the planet formed itself from rock, and over all the manner of creature and beast it spawned. For a time, they gazed over what would eventually be known as the earliest known humans, seeing them as any other creature born of the Earth. However, as humanity grew and prospered above most others, the First Children eventually realised that humanity would need a guiding hand; they knew humanity would play an enormous part in shaping the world, and would need to guide them as the world would one day become weary of humanity's burden.
Though the First Children were incredibly powerful (being near-omnipotent), cosmic as they were would allow them no connection to humanity other than being seen as Gods. Thus, they made their decision to become mortal. They would bind their cosmic essences to a newborn human child, living in complete symbiosis with the human soul residing within; mortal in body and immortal in spirit.
In doing so, they would be born, live and eventually die. They would understand mortality and so treasure it; and at the end of each life, they would reincarnate into another newborn human child, beginning the Reincarnation Cycle anew. And so, the Guardians were born.