Preheat oven to 350 degrees F (175 degrees C). Line two 12-cup muffin tins with paper liners, preferable dark-colored or Halloween-themed ones.
Combine cake mix, water, eggs, and oil in a large bowl; beat with an electric mixer on low speed until moistened, about 30 seconds. Beat at medium speed until batter is smooth and creamy, about 2 minutes. Spoon batter into the prepared muffin cups, filling each 3/4 full.
Bake in the preheated oven until a toothpick inserted in the center comes out clean, 18 to 21 minutes. Remove from oven and cool tins on a wire rack for 15 minutes. Remove cupcakes from the tins and cool completely on a wire rack before decorating, about 1 hour.
Spoon frosting in an pastry bag or a plastic bag with the corner cut off. Pipe strands of frosting onto the top and bottom of the cupcakes, leaving an oval eye shape exposed in the middle. Pipe 2 dots in the exposed middle for the mummy’s eyes. Place 2 chocolate chips flat-side up in the middle of each dot for the pupils.
Per Serving: 361 calories; 19.3 g fat; 48 g carbohydrates; 3.8 g protein; 28 mg cholesterol; 205 mg sodium