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batman, spiderman and superman on it. this is for same chiold i did the 3d spiderman in my pics for last year. so it needs to be awesome! thanks!!!

The first thing that comes to my mind is a 3 sided city building with:

One side has batman scaling down the side of the building using his bat hook wire thing.

One side has spiderman crawling down the building.

The last side has superman flying out of the building.

I love jewlykaye's idea! You could do the city skylines out of gumpaste to where the buildings go all around the cake. I've seen some skyline cakes on here that look great, then you could just add little fondant superheros on there!