The Great Ruin is the name given to the conflict which destroyed the Elder Race. A time of great cataclysm, it was during this time the Shattersea was created by the destruction and sinking of an entire swathe of the northern continent of Yaril. Great plagues and blights were unleashed by the powerful magic of the Elders, many of which persist to this day.
Koros, the seat of the Elder Race, was laid to waste during the Great Ruin, and great war beasts, mutant monstrosities and other inhuman soldiers created by Elder magic still roam the landscape.
Some speculate that the Narathi were created by the Elders during this time, so serve as dark wizards and commanders.