The "fluff" terrain type can be used to place special images on the map
board that have no effect on play, but improve the overall appearance of
the map. The level of fluff in the terrain, coupled with the exits that
are specified for the fluff, determine the image that appears. The full
list of fluff images available, and the level and exits needed to display
them, can be seen in the file, "data/hexes/defaulthexset.txt".
I searched through 35.21 but I couldn't find the file- where should I look?