The themes of cold and winter play a big part in Obormot's Reign of Winter, and the player characters will have a significant portion of their adventures in environments of ice and frost. It might seem, then, that (for characters of those classes that have the option to do this) using fire magic, and choosing fire-based powers, is a direct path to success.
Things aren't quite that simple.
It's true that fire melts ice, and fire effects (from the simple torch to the mighty fireball) are particularly effective against creatures of cold, structures made of ice, and so forth. But cold places have an affinity for magic of ice and frost, and an antipathy for fire; in a forest in the grip of a deep, northern winter, casting a burning hands spell is more difficult, just like it's harder to light a torch in a thick snowfall. Spells of cold magic, meanwhile, are enhanced in such environments — and particularly if the caster knows how to draw on the power of the frostfell, weaving it into her magic. These effects are felt in environments of natural cold, but even more strongly in places of supernatural cold, magical places where ice and frost are part of the land itself, and winter never ends.
So, there's a tradeoff: fire is more effective — it melts ice, and creatures of the cold fear it — but it's more difficult to use, and its power is weakened in a cold realm. Ice, meanwhile, is empowered, but the natives of the cold realms can weather it more easily.
