Kraks and all variety of kracks are zoanthids giagantis, they are not technically palys. We all call them palys, it is just one of the things in the hobby that goes on.
When I say Krak family or Krak traits it seems the zoas has a center of one color, and then a thick band of a different color, then a skirt that may match the middle color or be a different one.
Krakatoa OG: From what I have heard, finicky and prone to melt (not a surprise because it is expensive) only a few people with it left, still demands a pretty high price
Queen Krak/Jupiter paly: Same "family" with the rim before the rim type thing. These have become more widespread and are available at a lot of spots. Any price over $200 is way too much. Much less prone to melt, I have these midway in my frag tank and they seem to be pretty happy.
Blook Krak: Probably the newest one, red body with red rim before the skirt. Pretty cool zoa and looks to me (again my opinion) that it is in the same family. I have this one under low light at this time, but the person I bought them from said medium light. I will see how they do. I think these are around 100$ a polyp
Pink Krak: Named By WWC, while this zoa does exhibit the different color center and band, I am not quite sure (again in my opinion) that it is part of the Krak family. I just picked up my piece that I had split with a friend. They seem to be very hardy and grow pretty well and even if they are not in the Krak family per say, they are gorgeous in their own light. Price is a little all over with this one, as I have seen them on ebay and multiple sites at multiple prices. Just shop around.
Others: *** Kracks, Cherry corals something or other, and a few other names/ morphs. They do exhibit a color change right before the skirt but again it is not that defined of a band before the skirt starts. Again, amazing in their own way, but not the same.
Hopefully some of the OG Krak owners, and other with queens and pinks and bloods will jump in and you can get some serious answers.
