The defensive value of Difficult Terrain changes radically between maps where the ground is normal and maps where the ground is frozen/snowy. In normal weather Difficult Terrain is one of the best places for defense as there is a 0.55 multiplier for the attacker but a 0.75 multiplier for the defender. I don't believe any terrain has greater than that 0.2 differential, though other types have higher cover values. But in the snow maps both attacker and defender receive a 0.75 multiplier which makes it one of the *worst* defensive terrains, almost equivalent to sitting in the open. Is this as intended or is the attacker multiplier supposed to be 0.55 again for snow maps? There are some other terrain types with differences in their values between maps with normal weather and maps with snow but they are generally small... nothing at all remotely comparable to a terrain flipping from one of the best defensive terrains to almost tied for the worst.
"Difficult Terrain" looks to me like rocky, hilly terrain with ridges and stuff. Not something you'd expect to get hugely BETTER with snow all over the place.
See image.
