Fire is the Kethic element of heat and burning: the struck flame, the banked coal, the warmth that holds a body back from the cold. A shaper channels emotion through Yolus, the fire layer of the Elemental Planes, and flame answers, sparked from nothing, drawn taller, or pulled back off a roof it was a moment from taking. The feeling that feeds it is the kind that escalates and consumes: anger, passion, hunger, zeal. The hotter it runs in the shaper the larger the working, and a matched fury converts almost clean where a cooler, forced feeling scatters half its fuel and leaves a sullen flame that will not aim. Of the nine it is the hardest to hold steady, because that feeling runs the same way the fire wants to. Let the anger climb and the flame climbs with it, past the line the shaper meant to hold. Learning to summon a feeling on purpose and keep it just short of running away is the discipline all Kethic asks, and it is hardest of all to learn here. The cost comes after and is paid in feeling, not flesh: pour real rage into a wildfire and a cold, hollow hour follows, the passion spent until it fills back in.
Fire answers faintly almost anywhere, since the elemental stack presses against the whole world at once. Where a fire leyline runs close under the surface, though, the element bleeds through, and Kethic worked on that seam outperforms the same work done anywhere else. That same closeness can turn ruinous: the worst recorded rupture of the Yolus leyline was the World Fire, around 10 BSD, when the seam tore open under a single overreaching shaper and fire bled into the world faster than anyone could call it back. A smaller version of the same failure stands open now. The branch of the Yolus that surfaces beneath the Fleimrut Mountains tore in 2500 SD and never closed, the Fleimrut Awakening, and fire elementals still climb out of that breach into the range. The fault is local to the Fleimrut branch; the seam runs true everywhere else it surfaces. The Yolus leyline runs directly beneath Tarkhetan, under the Needle and the Old City stacked on it. The empire's Firemage Corps is built on that single fact. It is an order of fire-shapers whose work draws on the seam under their boots, which is also why the Corps cannot pack up and carry its edge to another city.
The same seam surfaces in the cathedral at the city's heart, where the Evertorch has burned without fuel since the Neferati founders kindled it six centuries ago from the sacred fire of Yaif. Whether the flame is no more than a leyline burn, as the empire's geologists hold, or whether something was given to light it and still pays to keep it lit, is a question the cathedral declines to settle. The heritage is not in question. The Kingdoms of Fire have not forgotten whose hands lit it, and fire-Kethic in the south still carries the character of Yaif's flame, plain to any Neferati priest who stands before it.