Divide white frosting in two bowls. Color one bowl with orange food coloring and the other one with green food coloring.
Frost 8 cupcakes with green frosting, 8 with orange frosting, and 8 with chocolate frosting.
Break apart Oreo cookies and remove the white filling. Place a Hershie kiss on each half half Oreo to make a witch hat.
In a microwave safe bowl, heat chocolate chips at 30 second intervals. Stir each time between heating until just melted and smooth.
Use a spatula, spread melted chocolate over the entire witch hat to be completely covered. It does not have to be perfect.
Spoon remaining melted chocolate into a zippered bag, or piping bag.
Set parchment paper on a baking sheet. Pipe the shape of a spider web. This is easy to do by making 3 even lines in a star shape. Then connect each line in a circle with a sweep of chocolate between each line.
Place chocolate spider webs in the freezer to firm up.
Break off ¼ of the digestive cookie. Pipe lettering onto the curved end of each digestive cookie.
Sprinkle chocolate Oreo crumbs over each cupcake frosted with the chocolate frosting. Stick the broken end of the digestive cookie into the cupcake.
Place each witches hat onto each cupcake frosted with the green frosting.
Remove spider webs from the freezer and carefully remove from parchment paper. Place onto the orange frosted cupcakes.
Arrange cupcakes together on a tray.