A cellular-automaton stand-in for the Belousov-Zhabotinsky reaction, a real oscillating chemical system in which a metal-ion catalyst flips between oxidized and reduced states. Three concentrations A, B, C live on a 200×150 torus and update as ∂tA=f(1−A)−kABAB−dAA+αkCAC(1−A)+D∇2A,
with cyclic counterparts for B (fed by A, drained into C) and C (fed by B, suppressed where A is high). Diffusion is a 9-point Moore-neighborhood average and reactions are evaluated per cell each tick. Because each species activates the next and the last inhibits the first, no steady state is stable — fronts of A→B→C→A chase one another across the grid, breaking into the rotating spirals and target patterns that BZ chemistry is famous for. The render is additive RGB: red from A, green from B, blue from C, so white regions are where all three coexist and pure-colour bands trace the leading edge of each travelling wave.