Omnithermal Equilibrium

Declare a mythic law of temperature over a place, creature, bloodline, forge, city, season, disaster, or battlefield. Define its principle with the GM: the city that never freezes, the forge that burns without fuel, the winter no flame can end, the fever that reveals lies, or the perfect balance that stops a catastrophe. It can be opposed only by Tier 10 temperature magic, divine intervention, or a story condition set when declared.