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A lurker in light resembles a small, jaundiced, emaciated elf dressed in muted colours, with large white eyes, and tiny horns on their head. Their pale wings are usually folded against their backs (as their movement is faster than their ability to blend with the light), and move with an inhuman grace. Lurkers are only visible in dim light; too much illumination will cause them to become invisible, leaving behind only eerie footsteps and mocking chuckles. When gathering in groups to prey upon multiple or powerful foes, they usually hide their numbers and present themselves as one individual to lure the target to illuminated areas. A lurker in light is three feet tall and weighs 20 pounds.12
Lurkers usually act as thieves and brutal killers. Sometimes they steal what they wish, and other times they might specifically harm the item's owners even when the item can be safely stolen. They appear to fixate upon certain enemies and objects, according to an inscrutable justice, and refuse to rest until the target is killed or taken.2
Lurkers hate druids, noble humans, those who deal with the First World, and especially gnomes: whole gnome communities, more than any other race, have been targeted by violent lurker attacks. However, sometimes, lurkers leave gnomes alone while attacking others around them.2
Lurkers despise dwarves, darkmantles, yeth hounds, shadows, and creatures from the Shadow Plane, attacking them and their masters and torturing them to death when possible. They have been known to work with undead creatures who cannot function in daylight, but disdain them, and have been known to abandon them at inopportune times.12
Lurkers in light were first spotted on Golarion in the late Age of Enthronement, in northern Ustalav and southern Cheliax before spreading across Avistan in the following decades. Initially, they only observed and shadowed people, but became violent when they realised their advantage. Tales tell of villages depopulated in a day, with phrases written in blood and the corpses of residents arranged into positions of feasting or spiral patterns. Since then, they have become more daring and selective regarding their targets.2
Lurkers in twilight are lurkers in light whose fundamental nature has been twisted, gaining an affinity for dim light instead of bright light.3