Preheat your oven to 350°F and grease a 9x13-inch baking pan. Follow the instructions on your Devil's Chocolate cake mix box. Combine the cake mix, eggs, oil, and water in a bowl, and mix it until smooth and well combined.
Pour the cake batter into your prepared baking pan, spreading it evenly to create a smooth layer.
In another bowl, beat together the butter and softened cream cheese.
Add peanut butter, and vanilla extract and continue mixing until it's creamy and smooth.
Slowly add in the powdered sugar, a little at a time, while continuing to beat.
Drop spoonful of the peanut butter cheesecake mixture onto the chocolate cake batter in the pan. Don't worry about perfection here; just go with it. Then, take a knife or spatula and gently swirl the two mixtures together.
Add 1 cup each of mini chocolate chips and reese on top of the mixture.
Pop your Earthquake Cake into the preheated oven and bake for about 45-50 minutes or until the cake is set, and a toothpick inserted into the center comes out with a few moist crumbs.
Remove from the oven and sprinkle the rest of the chocolate chips and reese all over the cake. Allow your cake to cool for a bit before serving.