Disaster / Destruction
When the Rifts between this world and the Realm of Water first ripped opened, causing water (fresh and salt) to pour into the world.
When the Rifts between this world and the Realm of Water first ripped opened, causing water (fresh and salt) to pour into the world. This caused water levels to rise around the world. This in turn caused a mass loss of knowledge and cultural regression, as the civilizations of the world struggled and failed to overcome the damages done.