A game in which the lives and deaths of cells in a square are divided into squares like a checkerboard.

  [rule]
1. If a cell is alive in exactly three of the eight adjacent cells, the cells in that cell can live in the next generation.
2. If a cell is alive in exactly two of the eight adjacent cells, the cells in that cell will remain alive or dead.
  3. Otherwise, the cell in the cell is killed by the next generation, or it gets too complex to die.