The space between the islands is known as the void. It glows with a constant light, called voidglow, exposure can drive people glowmad, mutating them into bestial, hate-filled savages.
Individuals can withstand different periods of exposure before going glowmad. People try and spend their sleep cycles out of direct exposure to the Voidglow. Travelers, unable to find other shelter, must sleep wrapped in a piece of heavy canvas to thwart its mutating embrace.
Exposure to the voidlight has debilitating effects; victims become angrier and more irritable until eventually becoming crazed and bloodthirsty. A man reduced to this state has but a few hours before transforming into a glowmad form. This has had a direct effect on the islanders, who are at least superficially, very polite to one another. Those who have a short fuse are viewed with suspicion.
Glowmad become twisted reflections of their previous selves, filled with rage and hate. Each race has a different glowmad form; drakin become murderous flying wyrmspawn; dwarves become earthbanes, anathema to stone and rock; elves become blight walkers, whose touch is death to plants; humans become savage blinded cannibals, able to hunt with a sixth sense; orcs become brutish ogres.
Wildlings are immune to the glowmad phenomenon and glowborn are created by it, originally being goblins. Glowborn and most glowmad goblins become ragers - berserk bestial humanoids.
Most islanders believe that becoming one of the glowmad is a fate worse than death itself.