The post title pretty much says it all, this time!  The castle is three tiers of marble butter cake, filled with light whipped ganache, and topped with Swiss meringue buttercream and homemade fondant.  Gumpaste towers with gilded roofs were then added.  The cake was completed with the addition of three gumpaste figurines: a dragon, attacking the castle, and a knight and princess defending it with sword and bow.