Reserve 1/4 cup of the frosting, then frost the cake.
Decorate the cake as shown in the picture with the fruit leather, sour straws, shredded wheat, and green and blue sugars.
Make the torii (gateway arch) with the rolled wafer cookies, fruit leather, and toothpicks, then press it into the cake.
Make the bridge by pressing two of the small pretzel knots into the cake, then attaching pretzel sticks to them with frosting.
Make the wall by inserting pretzel sticks into the cake.
Make the balance course by pressing sections of rolled wafer cookies into the cake and attaching a Spree candy to the top of each with frosting.
Make the balance beam by pressing the other two small pretzel knots into the cake and resting a pretzel stick between them.
For the tree, press a piece of the large pretzel knot into the cake, then add frosting and green-sugar foliage.
Add the candy pebbles and ninjas. If you like, put string licorice fighting sticks in the ninjas' hands.