Preheat the oven to 425°F. Generously grease all six cavities of a skull-shaped baking pan with butter, making sure to coat every crevice.
Remove and shred the meat from the rotisserie chicken. Add it to a large bowl along with the Frank’s RedHot sauce, ranch dressing, and dry ranch seasoning. Mix until thoroughly combined.
Roll out the first can of pizza dough and cut it into three thick, evenly sized pieces. Repeat with the second can of pizza dough to make six pieces total.
Press one piece of pizza dough into each greased skull cavity, gently molding it into the shape of the pan and leaving enough dough around the edges to close over the filling.
Spoon approximately 2 tablespoons of the buffalo chicken mixture into each skull. Top each with 1 teaspoon of whipped cream cheese, then divide the shredded mozzarella evenly among the six skulls.
Fold the excess pizza dough over the filling and pinch the edges closed to seal each skull.
Melt some of the remaining butter and brush it over the tops of the sealed pizza skulls.
Bake at 425°F for 13–15 minutes, or until the pizza dough is golden brown and fully cooked and the filling is heated through.
Allow the skulls to cool in the pan for a few minutes, then carefully remove them and flip them over to reveal the skull faces. Serve warm and enjoy!