Preheat the oven to 350 degrees. Line 18 standard muffin cups with paper cupcake liners.
In a large mixing bowl, combine the eggs, vegetable oil, and water. Whisk for 2 minutes. Slowly add the cake mix and whisk until combined – the batter should be slightly lumpy; do not over mix.
Divide the batter among the prepared muffin cups and bake for 15 – 20 minutes or until a toothpick inserted into the center comes out clean and the tops spring back when lightly touched. Let cool in the pans for 5 minutes and then remove and transfer them to a wire rack to finish cooling.
Frost the cooled cupcakes with frosting.
Twist the KinniToos to separate into two halves. Scrape the frosting from the middle and discard. Cut the bottom third off of half the cookies. Place the smaller cut portion in a plastic food storage bag along with the remaining cookie halves. Using a rolling pin, crush the cookies until they resemble dirt. Sprinkle the crumbs on top of the frosted cupcakes.
With the decorating icing, write on the side of the cut cookies that the filling used to be on. Make sure that the flat side of the cookie is the bottom of the tombstone. You can write things like RIP, Boo, or people’s initials. Stick the cookies into the frosting and prop up the back with a toothpick, if needed. Cut the gummy worms in half and stick a half into each side of the cupcakes. Place 2 jelly bean “grubs” on each cupcake.