Custom Cellular Automata rule with k colors

I did it. It's probably not the best implementation but works. Any feedback about how to optimize the code would be highly appreciated.

CyclicFunction[N_,matrix_,preylist_]:=Module[{cell=matrix[[2,2]],prey},prey=preylist[cell];If[MemberQ[Flatten[matrix],prey],prey,cell]]

CyclicCellularAutomaton[k_,size_,steps_]:=With[{preylist=Association@@Function[u,u-> RotateLeft[Range[0,k-1],u][[2]]]/@Range[0,k-1]},CellularAutomaton[{CyclicFunction[k,#,preylist]&,{},{1,1}},RandomInteger[{0,k-1},size],{{{steps}}}]]

BTW, I exported the evolution of the automaton as a gif but doesn't loop infinitely...why is that?

Every possible 2D function is enumerated in CellularAutomaton, so you need merely pick the function number. To get your desired colors, use ColorFunction, e.g.,

ArrayPlot[
 CellularAutomaton[{746, 
     {2, {{2, 2, 2}, {2, 1, 2}, {2, 2, 2}}}, 
     {1, 1}}, 
     {{Table[1, {7}]}, 0}, {{{150}}}],
 ColorFunction -> "Rainbow"]

or

ColorRules -> {0 -> Red, 1 -> Green, _ -> Black}

If you want to write your own function, look at the documentation for CellularAutomaton to see examples, such as:

CellularAutomaton[{Total[#] &, {}, 1/2}, {{1}, 0}, 5] // Grid