I recently was re-testing an old creature that I had created when I stumbled upon the fact that flying (under their own power) creatures are not affected by temperature while flying. What had happened was I was playing as an adventurer of a race that can walk/swim through magma for a short period of time but if they stay in for too long than they will burst into flames and die (this was accomplished by setting the heatdam of the creatures slightly less than magma temp). I had decided to fly down a magma tube (they don't need to breathe) and fight the imps within when I noticed that I seemed to not be being hurt. I than came down onto a part of the tube that protruded from the side and began walking instead of flying. Shortly after this I began to get the "you are on fire", "you are burning alive" messages. After walking for a little and gaining plenty of such messages, I launched myself back off of the side and began flying under the magma. The messages immediately stopped and I continued to go kill some imps. I then landed once again upon a part of the tube that stuck out and once again the messages continued to tell me that I was on fire. Another thing that I noticed at that point was that while I was walking I put out smoke like I was on fire, but while I was flying I did not.