It reminds me of squid ink. You could say there was a squid hiding behind the rock and shot some ink. But about the blood, I had asked about making realistic blood in water in bryce awhile ago and Vile has a pretty good method (b/c I think his looks pretty realistic). Hold on, let me fish out my old post... Ah, here it is: http://www.renderosity.com/messages.ez?Form.ShowMessage=381488 Anyway, Vile was supposed to be making a tutorial and I'm still waiting for it. But looking at those pics, it may help you get a little idea of what you're going for. Hope you find what you need & I hope Vile makes his tutorial soon. ~JKS