3 days in advance: Make gate, tree and bat. Tint Gum Paste: 8 oz. black, 8 oz. gray. Roll out 1/8 in. thick. Use patterns to cut out shapes. Let dry on cornstarch-dusted boards.
Also in advance: Decorate gate. Follow pattern to pipe tip 3 details in royal icing. Let dry.
Continuing in advance: Decorate bat, using Thinned Royal Icing. Work quickly, 1 section at a time, to prevent drying. Outline wings and legs with tip 2, body with tip 3. Outline section then immediately use damp brush to brush icing outward for shaded effect. Use tip 2 to pipe facial features and to overpipe main details. When dry, attach Cookie Stick to back with Thinned Fondant Adhesive. Let dry.
Attach gate to center front with fondant adhesive. Using full-strength royal icing and tip 3, pipe vertical fence posts, 3/4 in. apart. Pipe pointed bead on top of each post. Pipe horizontal lines 3 in. and 2 1/4 in. from bottom. Pipe a circle
inside each square. Using tip 3, pipe message and bead borders on top 2 tiers. Attach tree. Insert bat.