Preheat oven per directions on the box of cake mix.

Put the liners in the muffin pan. Set aside.

Following the directions on the box, add ingredients into a large bowl and mix all ingredients as instructed.

Divide the batter into two bowls.

In one bowl, mix in a few drops of purple food coloring. In the other bowl, mix in a few drops of orange food coloring.

Alternate between the purple batter and the orange batter and scoop about 1 tablespoon of batter into the cupcake liners until ⅔ full.

Put in the oven and bake for 22 minutes.

Check for doneness. (Insert a toothpick into the center of a cupcake, it should come out clean.) If they are not done, check again every three minutes until they are done.

Remove from oven and allow to cool.

Transfer to a cooling rack and allow to cool completely before frosting.

Using a standing mixer combine the butter, powdered sugar, heavy whipping cream, vanilla, and mix on medium speed until combined and smooth.

Mix in a few drops of neon green gel food coloring and mix until combined.

Scoop 1 cup of frosting into the piping bag.

Using the medium ice cream scooper, scoop some frosting onto the top of the cupcake.

Using a butterknife, lightly spread the frosting into a thick smooth disk.

Pour the halloween sprinkles into a small bowl and dip the entire frosting into the sprinkles.

Using the piping bag, pipe a dollop of frosting into the center of the cupcake.

Using the Unicorn Horn icing decoration, place it into the top middle of the frosting.

Place 1 "Ear" on both sides of the horn.

Serve and Enjoy!