Once each month the moon vanishes from sky; during this feared Moonless Night, the land is overrun by subterranean, light-hating creatures that ravage the countryside until the new dawn.

No one knows why the moon started disappearing.  But for 1,000 years now, once each month, the entire moon leaves space, as if under the effects of a teleport spell.

Astronomers aren’t sure when the moon first began its routine disappearances, as it always occurs on the night of the new moon, when it isn’t expected to be visible anyway. Eventually a sage of astronomy noticed that the moon wasn’t just dark, blocked from the sun, but it wasn’t in the sky at all. It seems that once each month, the moon simply vanishes; tides fall flat, and the planet goes without its moon for a period of 24 hours.  No one knows the moon’s destination on these monthly sojourns, or why it goes away. Some say the gods have again withdrawn their presence, while others believe the gods are merely toying with mortals for some enigmatic purpose. Each society in the Domain has its own chronicle of cultural myths to explain the departure of the moon.  These stories range from the preposterous to the probable, but even the most likely of them is mere conjecture.  Whatever the case, the moon’s disappearance has proven devastating to the Domain of Hawkmoon.

On the 30th of every month, when the moon disappears, strange creatures emerge from deep underground and wreak havoc on the population. These beings cannot abide sunlight; even the thinnest moonbeam (which is reflected sunlight) causes them terrible pain.  Thus they attack only when they know the moon is entirely gone from the sky.  They are intelligent, yet cannot be reasoned with, or bargained with, or in any way treated with anything but contempt.  Known by such names as the nocturals, the darklings, and the moon-tappers, these enigmatic monsters dig up from below and kill anything before them, dragging the bodies of their victims back down into the deep warrens of the earth.  There is no way to predict the location of the attacks; certain towns might go for months and never fall victim to an assault; but somewhere in the Domain, the nocturals come unerringly once per month. Little is known about these terrors, but over the centuries, residents of the Domain have learned to stay indoors during the dark hours of the Moonless Night, or the “hawkmoon” as it is sometimes called.  Over time, it has simply become habit that most folks take for granted:  on the hawkmoon of every month, lock your doors, shut up your livestock, and don’t come out till dawn.