The Great Wyrm's Grave

The Great Wyrm's Grave used to known as the Abyss. When the Great Gold Wyrm died, the gate was thrown wide for the demons. The Battle of Great Wyrm's Grave is considered the tipping point where the mortal races lost the world for good and were forced to focus on survival rather than victory.

Since then, the demons have spread far and wide, ripping open so many hellholes that the Grave is no longer as crucial to their power as it once was. That's fortunate for them, because the rumor is that the flow of demons from the Great Wyrm's Grave has slowed to a trickle for reasons no one in the Ark understands.