Prepare and bake cake mix as directed on package in two 9-inch round cake pans using water, oil and eggs. Cool 45 minutes or until completely cooled.
Place cooled cake rounds side by side with sides touching on 18x11-inch serving platter or foil-covered cardboard. From 1 cake round, cut crescent-shaped piece from outer edge for tail; remaining portion of cake round is the head. (See diagram.) Cut 2 small triangles from each end of "tail;" place on top of "head" for ears. Place "tail" to side of "body," trimming to fit as needed.
Spread frosting over cake. (If frosting is difficult to spread, heat frosting for a few seconds in microwave.) Cut green gumdrops and place on "head" for eyes; top with licorice pieces. Place peanut butter cups and red gumdrop on "head" for "nose". Place strip of fruit snack around "neck" for collar; add chocolate coin for tag. Break each piece of spaghetti into 3 equal pieces; insert at an angle next to "nose" for whiskers.