They hunt at Samhain, conscripting souls.
There are many versions of the Wild Hunt across folklore, a band of evil, misshapen spirits who prowl the darkest nights. The Sluagh haunt tales from Ireland and Scotland, telling of a flock of spirits that fly in like birds from the west. They usually hunt around Samhain, the precursor to what we know as Halloween, seeking souls to add to their ranks. Even death itself defers to the twisted, unholy Sluagh as it relentlessly hunted. Should you find yourself their target, it is only by putting another in your place that you can escape – an act which would probably mark you as even more suited to their collection of unrepentant, unforgiven sinners!
Image – Åsgårdsreien by Peter Nicolai Arbo, at Wikimedia Commons