Witches skilled with Pyrokinesis can create it by setting objects or people on fire. Madison Montgomery accidentally used this ability when she set Joan Ramsey's curtains on fire after being humiliated by her. She then began to practice this ability, and was able to light Fiona's cigarette and light the fireplace and candle at times throughout the season.
Kaylee, a witch, was shown to have been born with this power. She also used it in times of anger and rage, such as when she set her boyfriend on fire and almost, or might have possibly, killed him after he broke up with her, telling her she was 'weird'. Fiona used this power to light wigs on fire at Cornrow City when she was talking to Marie Laveau and Leslie, a witch, mentioned that Fiona mastered the Trial of Pyrokinesis. Anna Leigh Leighton used this ability to light the cigar on fire.
In a flashback to 1991, a young Hank Foxx is out witch hunting with his father in Chattahoochee Forest. Whilst his father lures a witch to him, Hank spares her after the witch, dirty and tired, begs for mercy. She then shoots a column of fire at him, burning him and almost killing him until his father arrives and shoots the witch in the head, killing her.
The Trial of Pyrokinesis was the only Trial not shown during the Seven Wonders. None of the girls demonstrated it, apart from Cordelia. She managed to pass the test easily by setting fire to the candle and the fireplace in the room, therefore allowing her ascension to become Supreme.