The formation of the Primordials and the Devils

The formation of the many Celestial races in the upper planes, leaked a new kind of magic through though the Astral Sea, which seeped first into the Plane of Elemental Chaos, which formed the primordials who gave first shape to parts of the Elemental Chaos using the power of creation from the formation of the new Celestial Planes.
  After this the power of Life filtered what was left into the bowls of the dark realm of Hell. This gave birth to the first Devils, who jealously sought dominion over all the realms, being heavily influenced by the negative energy in the Inner planes.
  The creation of additional planes also had an effect in the Lower Plane making 4 new Planes of existence. Forming the Planes of Acheron, Gehenna, The Darklands (now the Gray Waste), Carceri.

The creation of additional planes also had an effect in the Lower Plane making 4 new Planes of existence. Forming the Planes of Acheron, Gehenna, The Darklands (now the Gray Waste), Carceri.   Primordials are beings of great elemental power. As this new power of life and consciousness filtered away it also gave rise to many other elemental creatures, though the Chaos was not hospital environment, and so it was the Primordials who began to shape sections of the chaos, and give space for the other elementals to exist in someone peace.
These beings knew little of any other existence, many were content with what they could carve from the chaos, while others continuously sought more. This conflict was limited by the eternal state of chaos every creeping in.
  When the power arrived in the Lower Plane of Hell, it began to form Devils. These Devils developed under the dark influence of the Negative Energy in the Inner plane. Through the conduits of power that flow between the positive and negative energies, the Devils could see the state of the universe, and despised the Celestials for there decadence, and disregard for the universe.
These Devils sought power, and pursued it with a intense all consuming need. They found a way to make more like themselves, and these fiends and Devils began to plot evil deeds to overtake existence.