User blog comment:ChishioKunrin/Dust Speculation and Whatnot/@comment-3965075-20150108210330/@comment-73.42.187.52-20150109033213

I would bet water is the 4th of the four shown in that WoR: Dust pic, since green=Air, yellow=Lightning, and red=Fire, the only 2 likely candidates for color 4 are earth/water, and earth is rarely depicted in that kind of color