Pyroclastic

From Softology's collection · B6-8/S4-7/C10

Plumes erupt and burn out, each dying cell fading through eight states.

How the rule works

Each cell has 26 neighbours: every cell that shares a face, an edge or a corner with it (the Moore neighbourhood).
An empty cell comes alive when 6 to 8 of its neighbours are alive.
A live cell stays alive when 4 to 7 of its neighbours are alive; otherwise it starts dying: for 8 generations it fades, is not counted as a neighbour and blocks births, then the cell is empty again.
With 10 states in all (alive, 8 dying, dead), this is a Generations rule.

It starts from a random block in the middle of the box, 50% full and a third as wide as the box. Each run uses a new seed.

B lists the neighbour counts at which an empty cell is born, S those at which a live cell survives, and C the number of states. How to read a rule