So I made my first cake with the theme of a starfish on the beach. The starfish and the shells are made of modeling chocolate, the sand is ground up Nilla Wafers, and the water is fondant and buttercream, with a glaze of green and blue food coloring thinned with water and applied like paint. I also used chocolate rocks, because, well, they're just fabulous!
My second cake was both more simple and more complex, if that even makes any sense. It's made with white fondant and a deep purple buttercream, applied in a unique henna pattern that I made up as I went along. I put the frosting in a homemade henna cone in order to get the fine detailing and found that it was WAY easier to use than an icing tip. After all, since that's already how I do actual henna, I figured it was worth a shot. And it worked quite well! So well in fact that I am definitely going to use henna cones for all my cake lettering and detailing.