You won't be able to get Frost resist gear until you have silver, which comes after the swamp. You can get Wolf pelts from the Wolves there or use Lox pelts from the prairie, + silver. The wolf armor also gives frost resist, and you only need to be wearing one to get the effect. (Either the cape or a single piece of armor) Wolf Cape is probably gonna be easier. Idr the mats for the potion, but it's Bloodbags from leeches and.. something from the mountains ?