Preheat the oven to 350 degrees F.

Line a muffin tin with cupcake liners.

Add cake mix, water, vegetable oil, and eggs to a large bowl and beat on medium speed for 2 minutes, until smooth.

Divide the batter evenly between two smaller bowls.

Add black gel food coloring to one bowl and stir well until the color is even and as dark as you like. About 20 drops gets you a deep black.

Add red and yellow gel food coloring to the other bowl and stir well until you have an even orange. About 20 drops of red and 12 drops of yellow gets you a bold orange.

Now you should have orange batter in one bowl and black batter in the other.

Use a spoon to drop a small spoonful of orange batter into each cupcake liner.

Next, drop a small spoonful of black batter on top in each liner.

Alternate spoonfuls of orange and black batter until each liner is about halfway full and you've used up all the batter.

Lightly tap the pan on the counter to even out the batter, then place the pan on the middle rack of the oven.

Bake for 12 to 17 minutes, or until a toothpick inserted in the center of a cupcake comes out clean.

Let the cupcakes cool in the pan on a wire rack for 5 minutes, then remove them from the pan to finish cooling completely.

While the cupcakes cool, color the frosting orange with red and yellow gel food coloring. About 12 drops of red and 8 drops of yellow gets you a matching orange.

Mix well until the frosting is an even orange color throughout.

Fit a piping bag with a frosting tip, if desired, and set it in a large cup to fill with frosting.

Pipe or spread the frosting onto each cooled cupcake.

Add Halloween sprinkles and serve.