From the publisher's website:
Fire is arguably the most dangerous and most useful of the elements. Fire represents the power of civilization, through cooking, forging, ceramics, and the production of light. It also represents the power of destruction in that it is a threat to farm, forest, and city alike. Fire is the first magic, and the power to rub sticks together to create a living heat that breathes and moves is the first shaman’s trick.
Sometimes fire is the preferred tool of evil, with dragons breathing it, demons living in it, and evil warlocks using it to burn out their enemies. In other stories it is the primary tool of good, used to burn out the dens of wickedness and sin where only evil lives, and illuminate the darkest corners of the world. These approaches speak to the dual nature of fire: It produces both light and smoke, it can forge or melt, and it cooks or chars. Fire is an invaluable tool, but it is also a dangerous weapon that can turn on its master.
Of course, fire magic certainly isn’t under-represented in the core rules of the game. Indeed one of the most iconic spells in the game’s entire history is fireball, and the acquisition of that spell is a milestone in most wizards’ careers. But the very fact that fire is so ubiquitous among spellcasters often means GMs and players alike are looking for new ways to burn, char, and ignite foes. In addition to providing more typical burning-globe fire spells, we also took the opportunity to look at fire-related magic dealing in molten glass, smoke, steam, and the potential self-imposed dangers of playing with fire.