A p4 c puffer of the following form, which can be anchored on either side. Named for the output of its smallest iteration, the 2-2 dot puffer (shown below), which has an initial population of seven cells. The 2-2 dot puffer is the second most common naturally occurring puffer after the double dot puffer, followed by the 3-3 dot puffer. For a full list of possible iterations, see Iteration guides. Compare dot ship and key ship.

dot puffer.png

x = 6, y = 5, rule = s0/b2