I made this for my son's birthday today. Thanks to paoli96 for the tri-level cake idea! Chocolate cake with buttercream icing. The buildings are a gumpaste/fondant mix with yellow gumpaste windows. The Batman logo and birthday signs are gumpaste. I used a vodka/food coloring mix to paint on them. All the characters and Batmobile are toys. The cakes I make for my family are always the most fun! TFL!