Click flag. Three colors are randomly placed. Each color beats one other like rock, paper, scissors. Except two or more rocks must be next to a scissors to beat it, and so on. Group dynamics matter. It represents a type of ecology seen in some lizards and some bacteria also, in which each type is predator to one other type, and prey to another. Swirling clusters result. All updating is simultaneous.
I use pen to get around the limitation in the number of clones. See my several group rock-paper-scissors models that use clones instead. This version simulateneously determines future colors by using tiny pen marks with 3 new colors to code future colors. So the total colors required is six, but three are very small pen marks, so you don't see them easily. (My earlier version changes colors starting at the top and moving downward). Normally you need to use lists to do simulatenous changes but this method gets around that.
