Like other lesser spirits found in Kara-Tur, the bisan had two forms. Its most commonly encountered form was that of an insect, often a fruit fly or honey bee. In its other form, a bisan appeared as a beautiful woman. Her appearance was based on what species and age of tree she lived in. Their hair color varied from black to white, and their eye color was green. Bisan were able to cast polymorph self at any time to change form.
Like bajangs or dryads, a bisan was connected to her tree, her life-force drawn from it. If her tree was damaged, she would experience pain. If her tree was destroyed or died, the bisan would vanish. Her essence was then taken in by a nearby sapling. Such an essence could split into as many as four individual essences, making homes in separate trees. A bisan's diet was sunlight, and the nutrients absorbed by her tree. Bisan were always female.
Bisan were powerful spellcasters. They were able to cast, at will, become ethereal and turn invisible. Other spells a bisan could cast were animate wood, bane, bless, castigate, cause paralysis, elemental turning, elemental ward, ethereal jaunt, hold monster, ironwood, pacify, plant growth, quickgrowth and wood shape. A bisan was able to use the bark of her tree as the main component in a potion of healing.
Bisan only engaged in combat when their tree was in danger. They avoided direct confrontations, preferring to use their magic and guile to defend themselves and their tree. A bisan would attack in her insect form, since she retained the ability to cast her innate magic in this form. If cornered a bisan would cast curse on her attackers. Unless she were defending her tree, a bisan would retreat instead of engaging in direct combat.
Bisan primarily inhabited the forests and jungles across Kara-Tur, living in trees that they would fiercely defend. This defensiveness extended as well to other trees of the same species, treating them as though they were their home tree. For example, a bisan living in an apple tree would defend other apple trees in her area. Outside of Kara-Tur, they were known to occasionally be found at lower elevations of the Katakoro Plateau.
In exchange for an offering, humans were able to harvest material from trees in a bisan's territory, such as sap or fruit. A bisan would even allow humans to cut down a dying tree. Any human caught harvesting from a bisan's territory without making an offering did so at their own risk.
- Converging Lines (referenced only)
- James Wyatt (October 2001). Oriental Adventures (3rd edition). (Wizards of the Coast), p. 147. ISBN 0-7869-2015-7.
- Rick Swan (July 1990). Monstrous Compendium Kara-Tur Appendix. (TSR, Inc.), p. 7. ISBN 0-88038-851-X.
- Gary Gygax, David Cook, and François Marcela-Froideval (1985). Oriental Adventures. (TSR, Inc), p. 117. ISBN 0-8803-8099-3.
- James Wyatt (October 2001). Oriental Adventures (3rd edition). (Wizards of the Coast), p. 249. ISBN 0-7869-2015-7.
- David Cook (1990). The Horde (Volume II). (TSR, Inc), p. 119. ISBN 978-0880388689.