Pyrokinesis

Pyrokinesis was the ability to create and manipulate fire. Magic practitioners achieve pyrokinesis through spells which certain demons and other magically creatures had this as a natural ability.

Fire Conjuration
Fire Conjuration was the general ability to create fire.
 * Willow Rosenberg once magically lit a barbecue, however, this somehow caused the weather to rain.
 * During her time as a dark witch, Willow created a fireball from the wreckage of the Magic Box and make it track down Andrew Wells and Jonathan Levinson destroy them. Though Buffy Summers managed to save them, the ball caused a rather large impact, breaking a hole into the ground of the Sunnydale Cemetery and trapping Buffy and Dawn within it.
 * Xander Harris once, accidentally, set a book on fire by casually reading out the words "Iibrum incendere".
 * Beck was granted with pyrokinesis when she bonded with a Fire Elemental.
 * As part of the Demon Trials, Spike had to fight a demon with fiery fists.
 * After murder a number of people at the Sky Temple, the Beast used their corspes to form the Eye of Fire, thus conjuring a rain of fire.
 * Lorelahn had fired arms which he used to fight.

Disintegration
Disintegration refers to completely destroying an object's or being's structure by engulfing it with heat or flames.
 * The Judge could  'burn' the humanity out of any being. This would cause the victim to literally 'burn' and disintegrate in a matter of seconds. However, beings with sense of humanity was safe, as with the case of Angelus.
 * After murdering Warren Mears, Willow set his body alight, causing it to burn into nothing.
 * The lower being D'Hoffryn was able to kill one of his own Vengeance Demons, Halfrek, by having her burst into flames into nothing.

Combustion
Combustion refers to causing an object or person to spontaneously catch fire.
 * Catherine Madison made a Sunnydale High student's hand spontaneously combust during an audition for the cheerleading squad.
 * The demon Sweet could alter reality in an area to make its people burst out song and dance. This living musical would cause some individuals to dance so intensely they would combust in flames and burn to death. This happened to an unnamed tap dancer and almost to Buffy during her performance of "Something to Sing About".

Heat Generation
Heat Generation was the ability to emit heat.
 * The females of the Oden-Tal species could generate heat due to their ko, allowing them to fry other beings to death with a touch. This was uncontrollable during the stages of maturation and they were required to be kept in cold containment.
 * When Dark Willow hunted after Warren, he managed to trap her in some sort of cage made of water. Channeling through her eyes, Willow generating heat, causing the cage to break down.

Fire Breathing
Fire Breathing was the ability to release a stream of fire from once's mouth.
 * When Dawn was briefly possessed by the demon created vis thermogensis, she attacked the other Scoobies by breathing fire at them.
 * Dragons naturally could breath fire.
 * Kelgor's familiar resembled a giant bird that could breath fire.