Im looking to take some PC's to a new region of a world we are building and I would like to make it a very difficult environment to sustain in. I am looking for feedback on what Dc i should make the fortitude saves and if they fail what would be the negative impact on the pc. The players are each playing a level 3 character and a level 10 character. Im sure the levels 10's would pass it pretty easy except for maybe a caster or two and im ok with this.I was thinking a dc 12 fort save or be slowed for 1d4 hours or something along those lines. What do you guys think?