Cold and wearing cotton....if you are talking about actually killing a hunter. Weather can ruin hunting, like too hot during the rut, or so much rain that it washes the sent from the cows or makes the game hold up. The wolves are often running out game completely out of some areas here in Idaho now. Hunting with client hunters who didn't beleive you when you told them they needed to be in good shape to hunt our rugged area. And bad attitudes.