Artificial Avalanche
Heavy snows can put local settlements at risk, and the best way to mitigate the danger is by triggering a controlled avalanche instead. Those who attempt this find the environment as much of a struggle as the act itself.
Biting Cold. At the end of every hour spent traveling through this area, a creature makes a Constitution saving throw (DC 5 + 2 per previous save) or it takes 4 (2d4) cold damage.
Spell Solve. Spells or effects that deal at least 10 points of thunder damage within a minute trigger the artificial avalanche and a success— unless they are in its path, which triggers a failure.
Well-Prepared. Adventurers equipped with climbing gear or similar equipment gain an expertise die on check to overcome this challenge.
A group Survival check is required to safely arrive at the intended site. Those who do can trigger the avalanche by making a ranged attack to throw explosive material or by an Athletics check to perform a slope cut with skis or similar equipment.
Critical Failure. The adventurers have drastically miscalculated. Each take 4 (1d8) cold damage and 4 (1d8) bludgeoning damage as they are buried in snow and must hold their breath. Each round they make a Strength saving throw to free themselves. On a failure, they are still trapped in snow and must hold their breath for an additional round.
Failure. The adventurers miscalculated, but avoid the worst of the slide. Each takes 4 (1d8) cold damage and 4 (1d8) bludgeoning damage.
Success. The adventurers successfully trigger the avalanche.
Critical Success. The adventurers successfully trigger the avalanche and are blessed by the gods of winter. Roll on the Boons and Discoveries table.