The Freedom Fighters prepare a defense system of catapults in the Great Forest, but find them to be lacking strong enough structural support. Princess Sally sends Sonic to Robotropolis to salvage metal cotterpins. Tails wants so desperately to help his hero, so Sonic allows him to venture with him into the "big city". Through Sonic's intrepid heroism, and Tails' ability to hide in a backpack, the Freedom Fighters manage to thwart Robotnik's Buzzbomber bomb assault on their hidden home.