I made this cake because my daughter wanted a octopus cake for her Tiki birthday party. It was actually very easy.
1 large round cake
1 medium round cake
2 jumbo muffin size cakes
I cover the bottom layer with icing and then fondant. I lightly buttered the fondant and sprinkled brown sugar to make it appear as sand. Next I covered the next layer with blue tinted fondant and stacked it on the bottom sand layer. Then I took the over sized muffin cakes and stacked them with the tops together (so one bottom is on the counter and the other was facing the celing).
I then shaped them to look like a octopus head. Then iced it and covered it with purple fondant. I took the remaining purple fondant and rolled it, to make legs. then used some white fondant for the eyes.