What a great cake, your son must have been so happy!
How did you do the vertical part? Does that have cake in it? Cardboard supports? And what flavors were the inside of the cake? Is the black a chocolate-based fondant?
It’s funny, I had been thinking that I couldn’t imagine a cake with black fondant, but now I see that it makes perfect sense! And I don’t know if there were any issues with fondant coloring their mouths, but boys of that age probably thought it was great fun if their mouths did turn colors! My daughter loves it when a lollipop turns her mouth blue!