Dreamblade treats these as some kind of ectoplasmic critter, but I decided to go with a sea-blue scheme and make them water-elemental types with the repaint.
The main sticking point on these models are those tentacles they're waving about, as they're much too thin and flexible to be worth painting as is. The solution was simple, take a length of thick "hobby" wire (which came out of the floral department at A.C. Moore's) and wrap it around the original tentacle, then use a few layers of accelerated Zap-a-Gap to blend it into the contours of the rest of the model. You could use putty instead, but Zap glue hardens into very fluid shapes when you hit it with accelerant, and it's very, very quick. (Don't do inside though, unless you enjoy birth defects and cancer in the family.)