Included below are some additional rules and thoughts on using the psychic talent of pyrokinesis in COC/ DG games...
I confess to being influenced by comic books when I designed the way pyrokientic flames behave, but those aspects of the talent can easily be discarded if they don't suit your game. Please enjoy!
Also called firecasting, as made famous by the film "Fire Starter" starring Drew Barrymore (must viewing for anyone whose game play features pyrokinesis), pyrokinesis is the ability to project blasts or balls of fire, and to cause objects to spontaneously combust through exertion of will alone. It is fairly common in cases of poltergeist phenomena, which feature numerous tiny, inexplicable fires.
Pyrokinesis is an offensive talent, and the base rating is equal to the character's DEX score, since the base rating with an offensive talent is also the basic chance to hit. The player may also spend Magic Points to increase the chance to hit at a cost of 1 Magic Point = +1% increased chance to hit on a case-by-case basis. Of course, the base rating of pyrokinesis may be increased just like a skill, in accordance with Call of Cthulhu's established skill-improvement-through-use procedures. Base range is 10 meters, plus 1 meter per Magic Point spent explicitly to increase range.
Damage is inflicted as follows:
Pyrokinetics can also cause a number of SIZe points worth of combustible materials (paper, wood, gasoline, etc) equal to its POW/3 to spontaneously combust. Pyrokinesis is all about causing fires and flames, not necessarily heat. Further, pyrokinetic fire is composed of psychic energy, and will burn when normal fire shouldn't, such as conditions of reduced oxygen, or poor quality fuel (like a human body).
A pyrokinetic can also create different types of fire, by rolling less than its POW X 5 and expending a Magic Point. For example, a pyrokinetic can create quantities of "cold" or theatrical fire: flames cool enough that they won't easily kindle even paper, but which will look and act like real flames. On the other hand, pyrokinetics can also create blow torch-like flames. Pyrokinetic fire has a normal temperature of roughly 450EC, or about the temperature of burning wood alcohol. By rolling less than POW X 5, the pyrokinetic can push the temperature up 10EC per Magic Point spent. Such hotter, more narrowly focused flames can be used to cut metal or even concrete.
By rolling less than its POW X 5, a pyrokinetic can create one cubic foot of fire per magic Point spent, and cause this fire to assume a variety of shapes by force of will alone. Arrows and even words (for sky writing), walls or discs of fire, blocks, non-missile balls, rings, and even cages (for restraining foes) are all conceivable shapes. Although the only practical limit is the player's imagination (and Keeper common sense), Keepers are perfectly justified in calling for Idea rolls when pyrokinetic sculpting is undertaken.
Pyrokinetic fire looks like normal fire, although hotter "blow torches" tend to be blue, like burning acetylene torches.