It's a 6 tier square cake covered in marshmallow fondant with royal icing decorations...
And let me tell you, this has been the most painful cake I've ever made.
I don't know if it's because I've had to roll out all that fondant by hand (in addition to actually making the fondant; there's a lot of kneading involved) or because I piped 6 tiers worth of decorations in one sitting, but my muscles are so sore! (I guess it could be because I'm trying to go the gym everyday too...)
But, no pain, no gain. And this cake is going to be totally gorgeous and worth all the trouble :)