What to watch
- The front advances orthogonally at c/2.
- The back end leaves debris behind instead of cleaning itself up.
- It makes the difference between a spaceship and a puffer visible.
Growth patterns
An almost natural c/2 puffer that leaves debris as it moves.
Pufferfish is a compact way to introduce puffer behavior before sending users into the infinite board. It moves like a spaceship but does not leave a clean empty wake.
Use it before the advanced infinite-board examples that need more room and longer runs.
Open the pattern in the lab, reduce the speed, and use single-step mode when a phase change is hard to see. The green preview marks births in the next generation; red outlines mark live cells that will die.