WORK IN PROGRESS
Quickly after I found out about CA and Golly, I found out about rules like Diamoeba or Stains. I have since been interested in rules that generate solid white shapes with interesting edge dynamics and movement.
I decided to put the interesting rules I have found here, because I don't think they are deserving of their own page, since they are not interesting because of any engineering or spaceships or any of the usual stuff, but because of their peculiar and interesting dynamics.
This rule generates quadrilaterals with which have one bouncy side. To see what I mean, run this pattern.
Did you see that? The top edge of that quadrilateral bounced a bit, which I find nice. This bouncing behavior is amplified in other rules...
This rule has many (possibly infinite) c/5d spaceships of different periods. The highest period one to have shown up so far is this period 970 (194c/970d) ship
You can see how it works, a single engine with some companions on the side, and a fluctuating tail. Nearly all the c/5d's in this rule work like this. I say nearly all, because there's one c/5d that seems to be unique. It's a p5 c/5d. Yeah, it doesn't sound as exciting as the others, but it seems to be unique.
This rule also harbors a unique c/24o, surprisingly:
One more, this rule contains two known c/19d spaceships (Which is also rather surprising), and looking at the similarity between the two known ones, I propose that there is a family of c/19d's, somewhere out there. We just haven't found them yet.
"That's a beautiful rule. Watching it is like watching a battle going on between two types of patterns, the diamonds and the combs. The diamonds seem to have the upper hand most of the time, but every now and then a comb will make a valiant attempt to take over, only to succumb once again to the hungry diamonds."
— wildmyron, https://conwaylife.com/forums/viewtopic.php?f=11&t=803&p=41146#p41072
Original mention: https://conwaylife.com/forums/viewtopic.php?f=11&t=803&p=41146#p41062
The quote above provides a poetic summary of the dynamics of this rule, but here are the two tribes, the diamonds and the combs.
This rule creates growing diamonds which are occasionally assaulted by the emergent comb patterns. Here is a sample:
It looks a bit like a cloth waving around in the wind.
This rule has one known spaceship found by Goldtiger997 from a soup search. It is of speed 4c/150d (Simplified 2c/75d):
Original mention: https://conwaylife.com/forums/viewtopic.php?f=11&t=803&p=41146#p41059
This rule is similar to slugs in that it makes bouncing quadrilaterals, but in this rule they sometimes get very large. However, the larger ones seem to behave differently. Here's a large sample, it somewhat reminds me of folding paper.
This rule doesn't really have much more to offer, unfortunately.
This one is like a battle between the Death of a Square and the growth of a square, but Death wins. At the first few generations, a solid white rectangle with some perturbations at the edges is generated, and those perturbations slowly erode the rectangle, but the rectangle fights back and tries to grow. This moves the rectangle around. Here's a small sample:
It is best experienced at larger soup sizes, so fire up Golly, set the scale to 2:1, and make a large soup.