Evil Weather (3.5e Variant Rule)
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Evil weather is a supernatural occurrence brought about by a variety of supernatural curses, hexes, and divine machinations (first detailed in the Book of Vile Darkness). The term refers to any sort of (evil) supernatural environmental condition, including both standard weather effects and associated phenomena, such as fog, altered light conditions, etc. The following are rules for additional kinds of evil weather, including descriptive information about the weather, its causes, and its in-game effects.
Types of Evil Weather