The Black Lotus

A flower most rare and coveted, the black lotus is a treasure to magic-users of all kinds, as well as to certain kinds of pleasure-seekers.

"The Coven-Master gave to me a phial Of the dread opiate that is the key To dream-gates opening upon a sea Of acherontic vapours; mile on mile Stretched ebon coasts untrod, wherefrom aspire Pylons of rough-hewn stone climbing to skies Alien-constellated, where arise Grey mottled moons of cold and leprous fire. I saw -- and screamed! And knew my doom of dooms Learning at last... where the Black Lotus blooms."

Lin Carter: "Dreams from R'lyeh"

Growing in humid, reptile-infested marshes of the South and East, the black lotus is likely the most expensive item on Weirth, pound-for-pound. The flowers, pollen and roots of the various lotus-plants are all useful to magic-users and poisoners, but the black lotus holds a special place.
The flowers and stem of the plant are burned in a magic-user's focus bowl, producing a thick, bright-green smoke that seems to glow with an inner light. When burned in the dark the thick, cloying smoke does indeed illuminate an area of five feet in radius, about the source.
The smoke is poisonous, except to certain magic-users who have made certain preparations. When properly ingested, the smoke can be a powerful restorative for magic-users, both for recalling magic spells, regaining energy, or preparing to cast new spells. Unfortunately, there is a price to be paid (in SAN).
Black Lotus root, dried and powdered, can be used to confuse and befuddle one's enemies, poison small creatures, or even enhance hypnotic suggestion. Great care must be taken when handling or wielding black lotus powder!
Magic-users and Alchemists and the Sisterhood of the Raven will pay handsomely for the black lotus, whole plants or just portions, making the black lotus a very lucrative trade good.