The will-o'-wisp appeared to be nothing more than a hazy ball of light, colored white, blue, violet, green, or yellow, glowing as brightly as a flaming torch. As such, it was easy to mistake one for a lantern, torch, or dancing lights. Especially within the foggy marshes they tended to inhabit. They tended to take on a blue, violet, or pale green hue whenever they were engaged in combat.
In fact, their faintly glowing bodies were just transparent balls of spongy matter, measuring 1 foot (30 centimeters) wide and weighing around 3 pounds (1.4 kilograms). Although they had no vocal organs, will-o'-wisps could vibrate to emit a ghostly sound, with which they could speak.
Boggarts were believed to be immature forms of will-o'-wisps. Unlike their mature counterparts, boggarts could take on a shape of small humanoids and lure their prey and a shape of a smaller but brighter wisp. Another major thing that differentiated will-o'-wisps and boggarts was that the immature forms needed to devour flesh and the life force of their prey.
These creatures could alter the brightness or dimness of their bodies' glow. This ability was used to confuse their prey. A will-o'-wisp could even extinguish its glow, becoming for all intents and purposes invisible to all except creatures who see invisible objects. They typically did the latter whenever they were surprised or frightened.
A will-o'-wisp would avoid combat if at all possible, but would attack with electric shocks if pressed.
These creatures subsisted upon the powerful emotions that are associated with fear, panic, and death.[note 1] They would often seek to lure creatures away from safe paths, into perilous situations so they could feast upon their desperate emotions.
Will-o'-wisps were typically found in deserted, dangerous places where ones movement could get inhibited. Such as bogs, fens, swamps, as well as swampy dungeons and dungeons full of quicksand or pit-traps.
In early Eleint of the Year of Lightning Storms, 1374 DR, a will-o'-wisp cooperated with the Sharran cultists at the Lost Refuge in the Vast Swamp. It posed as a torch outside the gatehouse and haunted the surrounding swampland, while helping to defend the base from intruders. It was presumably destroyed by adventurers in service to Mystra when they assault the base.
- These creatures were originally described in Monster Manual 1st edition as feeding upon "fleeing life force".
- Curse of the Azure Bonds • Dungeon #71: "Dreadful Vestiges" • Pool of Radiance: Attack on Myth Drannor • Cormyr: The Tearing of the Weave • Dungeons & Dragons Essentials Kit
- Video games
- Eye of the Beholder II: The Legend of Darkmoon • Neverwinter Nights: Tyrants of the Moonsea
- The Paladins
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