Yield: 15 servings (3 points per serving for blue, green and purple)
Preheat the oven to 350 degrees F.
Add the blueberries and Splenda to a mixing bowl and stir.
Add the cake mix and Sprite Zero to a mixing bowl. Use a hand-held mixer on low for 2 minutes.
Spray an 8x10 baking pan with no-stick cooking spray. Add the blueberries and make sure they are spread out evenly.
Pour the cake batter evenly over the blueberries.
Bake according to the directions on the box. Once the cake cools, flip it out of the pan (upside down) onto a serving platter. Enjoy!