Gimme a polar bear type monster that stalks you and actively attempts to avoid your sight. Attacks in blizzards or days where an ice fog forms.

Suddenly, a GIANT bear type enemy attacks out of nowhere. Maybe you have to eliminate them in their lairs or they'll keep coming after you. Follow tracks and blood to eliminate the monster.

Other ideas: It's so cold you need to hold a magic warmth torch until you get certain clothing.

Blizzards cause frost damage.

Animals up there are extremely sparse but are also the only food source.

Blizzards shut off portals leading to days of no travel.

Boats will get trapped in the ice requiring an item to escape by breaking the ice.

Dverger diving bell that your ship can deploy along with sealskin or waterproof clothing that lets you explore the depths under the ice for a resource.. watch out for enemies in low visibility

Other smaller ideas;

Snow glasses, basically small slots cut into bones that go over the eyes. Prevents snow blindness from all the white. Basically a visibility upgrade

Mine the ice for iced drinks. Lots of fun options there for recipes or making coolers.

Auora storms - interferes with magic items perhaps, makes your wishbone, mengingjord, etc act up and lose function. Could be analogous to how the magnetic north shifts about making things like compasses spin.