Nonstick spray a 9 by 13-inch baking dish.
In a Dutch oven or sizable saucepan, melt the butter over low heat. Add the marshmallows and food coloring and cook, stirring, until the marshmallows are completely melted, about 3 minutes. Turn off the heat and fold in the rice cereal. Place on the prepared baking dish. Apply nonstick spray to your palms and pat the mixture into an even layer. Refrigerate for about an hour, or until firm.
To release the treats, flip the baking dish onto a chopping board and give it a light tap. Trim the sides, then divide the rectangle in half to get two long rectangles. Make 5 equal, 2-inch broad pieces out of each rectangle. Line a rimmed baking sheet with wax paper.
Put the chocolate chips in a microwave-safe bowl. Microwave for one minute, stirring halfway through, until the food is just melted. Use a toothpick to move the chocolate around to form unique hair patterns. Put a dot of icing on the back of the candy decorations to stick on facial features. Use another dot of icing to stick a mini marshmallow on the sides of each head for neck bolts. Draw on additional features with the icing. Store in a cold, dry area or serve right away.