For this set of images, I achieved the fire image effects completely in camera. Not everything fantasy needs to be digitally retouched. Using a combination of lighting and camera settings, I was able to blur and freeze parts of the image. Gels and the types of lights used gave the red/orange coloration.
In this ice image, I created a partial set for the session to give a three dimensionality to the image, then used a few stock elements and digital editing to complete the look in post. By creating a set, you can have a foreground, middle ground, and background. Whereas, adding elements in post usually only applies to backgrounds. I say "usually" because there are always ways to break the norm. In this case, the "snow" is really on the ground by Deirdra. I also had some branches on the set.