The Great Darkness was a time at the end of the Storm Age and before the divide between the gods' realm and the realm of mortals.
Lore[]
When the chaos gods Thed, Malia and Ragnaglar joined together as the Unholy Trio, they unleashed chaos into the idyllic Storm Age, and started the Great Darkness. In those times, chaos creatures roamed the earth, destroying everything in their wake. The creatures were numerous, and many people died fighting. And with the birth of Wakboth the Devil, the people lost hope entirely.
When Orlanth saw the destruction of all he had built, he could not sit idly by. He embarked on the Lightbringers Quest, accompanied by seven other gods, who were later called the Seven Lightbringers. At the end of their quest, they gathered all the gods and Arachne Solara created a net with which they captured Wakboth the Devil, destroyed him. Arachne Solara then gave birth to Time, and the gods agreed that the world of the mortals and the realm of the gods were to be separated, so that nothing like this would ever happen again.
Myths[]
You can read more about the Great Darkness on your 
Lore Screen in game, or here:
- The Great Darkness
- The Lightbringers Quest