Flame spirits were related to fire elementals. They appeared as contracting and expanding spheres of flame. Flame spirits had two oval shaped eyes, which were its only facial feature. They were capable of speech and when they spoke it sounded like steam hissing from a pipe.
Each type of flame spirit had a slight difference in appearances. The color of a greater flame spirit shifted constantly from green, red and yellow, while a lesser flame spirits flame was dull orange and a least flame spirits brilliant white. Each had a tendril of fire that randomly emerged from the ball of flame. This tendril was 5 ft (1.5 m) in length for greater flame spirits, 3 ft (0.91 m) for lesser flame spirits and 2 ft (61 cm) for least flame spirits.
Greater and lesser flame spirits were vicious in combat, ruthlessly attacking a target without mercy. Their flames acted as magical fire thus were able to cause a large variety of items and materials to combust. Least flame spirits were relatively passive and peaceful.
Flame spirits were most often summoned in Kara-Tur by evil wu jen, who tasked the flame spirit to act as a bodyguard or act as a furnace for alchemy and magical experiments. Least flame spirits were often used as sources of light.
Flame spirits could only by summoned either in or near open flames. Greater fire spirits could be summoned with a large fire, lesser flame spirits had to be summoned near a volcano, and least flame spirits could be summoned with a lit candle.
Greater and least flame spirits were able to consume any combustible material, while lesser flame spirits were only able to eat volcanic material such as ash or basalt.
The ashes of combustible material consumed by lesser and least flame spirits could be used as components in the creation of magical items. The ash from a piece of parchment that was consumed by a lesser flame spirits was used as a component in creating spirit chasers, while the ash from a piece of silk that was consumed by a least flame spirit was used as a component in creating a charm of protection from fire.