The Midday Night

The Midday Night refers to a double eclipse that occurred in the fall of 223 AA. It has been the only double eclipse since the Arrival and It had a significant effect on the Eldritch Pits. Monsters began to spew from all of the pits. Hundreds of every kind imaginable came pouring out in all directions. The eclipse lasted nearly an entire day.
It took years to bring the monster population back to normal. While an eclipse is by all accounts a natural phenomenon the double eclipse seems to follow its own rules. This event ended The Year of Blood and fundamentally changed The Grel. They created The Lunar Siblings religion and began to form a real society.