Now, before you read this, there are valid concerns such as Lag that mean this has to be tested in Alpha. They need to see if having a zone where it is constantly snowing liek Hoth in Star Wars is all they can do or if Lag permits, could they have seasons in the world, whereby it would get both colder and hotter in places and this would change how the world reacts. Taking this a step further, here is a snippet from the Pantheon team. I hope they can do this as it would be groundbreaking.
One of Pantheon’s tenets is ‘Engage the World!’ When we talk about being a PvE MMO, our definition of ‘environment’ means a lot more than just fighting NPCs -- players will be contending with the world itself. Some regions will be very hot or cold. Some areas within a zone might be enchanted with complete darkness, or silence (meaning spoken spells won't work), or poison or miasma. Small tornados could travel through a region, compelling players to work their way around them, not through them, lest they take significant damage. Also, certain spells may work better or worse (or even only work) depending on the climate or atmosphere -- for example, a 'Call Lightning' spell could deal more damage than a typical ‘lightning bolt’ spell but could only be cast if there is a storm in the region.
Thoughts ? Has anyone seen something like this done before ? I remember in Vanguard, Fireball spells would travel less far over water for example.