Manipulate[
 init = RandomInteger[colors - 1, {100, 100}];
 ArrayPlot[
  CellularAutomaton[{rulenumber, {colors, 1}, {1, 1}},(*{{{1}},0}*)
   init, {{{steps}}, All, All}], ImageSize -> {490, 490},
  ColorFunctionScaling -> True,
  ColorRules -> {0 -> White, 1 -> Black, 2 -> Blue, 3 -> Green}],
 {{colors, 4}, 3, 5, 1, ControlType -> SetterBar},
 {{rulenumber, 1412490}, 0, 1452490, 1, Appearance -> "Labeled"},
 {{steps, 800}, 2, 10000, 2, Appearance -> "Labeled"},
 SynchronousUpdating -> False]