Heat oven to 350F (325F for dark or nonstick pans).
Place paper baking cup in each of 24 regular-size muffin cups.
Mix and bake cake mix as directed on box for 24 cupcakes. Cool 10 minutes; remove from pan to cooling rack. Cool completely, about 30 minutes.
To make spiders, press 4 licorice pieces into each side of 12 of the cupcakes, letting about 1 1/2 inches hang over side of cupcake.
Spread tops of cupcakes with chocolate frosting; sprinkle with black decorator sugar crystals. Slice black gumdrops in half for faces. Press red cinnamon candies in center for eyes.
To make owls, spread chocolate frosting on remaining 12 cupcakes. Use candies to form eyes, beaks and feet on each cupcake.
Cut chocolate wafer cookies into quarters; place wafer pieces, triangle points up, behind eyes for ears.
Cut wafer cookies into thirds for wings; place on cupcakes. Store loosely covered.