Fire

The element of fire was one of the four fundamental building blocks of matter, both useful and dreadful, warming and consuming, changing and purifying. Despite elements generally playing a neutral role in the cosmos, fire was seen as aggressive and evil by many.

Cosmology
Fire manifested its position in the cosmos as the Elemental Plane of Fire, one of the Inner Planes. The element was also represented there in living form as fire elementals.

The ruler over the portfolio of fire in Faerûn and Zakhara was the elemental lord Kossuth, while it was held by Tezca in the Maztican and by Girru in the Untheric pantheon. Among the Lords of Creation worshiped in southeastern Kara-Tur, Agni held dominion over this element. Moradin of the dwarves and Flandal Steelskin of the gnomes also had a special interest in fire as it was used in the forge. Talos, the draconic deity Garyx, and the giant power Surtr administered the destructive side of fire. The evil archomental Imix also worked to wrest the claim over the element of fire away from Kossuth, but the greater power remained firmly in control.

School of elemental fire
Many magical spells utilized the element of fire. Elemental fire was recognized as a "school of effect" (rather than one of the eight traditional schools of magic). Wizards specializing in this school were called fire elementalists. Fire was opposed to the element of water, both as a school of magic and as a worldview.

Magic-users in Zakhara had a similar but not identical notion of fire magic in the form of the province of flame.

Likewise, the wu jen of Kara-Tur divided spells into five elemental groups, including fire.

Divine fire magic
A number of deities granted divine spells that relied on the element, either in the form of the elemental fire sphere, or the fire domain.

Celestial bodies
Spacefarers also used the four elements to distinguish different types of celestial bodies present in the crystal spheres. Fire bodies were often found at the center of a crystal sphere, giving light and warmth to all its worlds. The sun of Realmspace (as its only fire body) was just such an example.