Line a baking sheet with parchment paper. Place a large nonstick pot over moderate heat, add 1 cup chocolate chips and peanut butter and stir until completely melted and smooth. Remove from the heat and add the marshmallow fluff, stirring until completely combined.
Add the cereal and gently stir with a rubber spatula until evenly coated with the chocolate peanut butter mixture. Add the powdered sugar and mix until evenly coated. Pour out onto prepared baking sheet and spread out evenly.
Sprinkle the top with the remaining 1/2 cup chocolate chips, marshmallows, graham crackers, M&M’s, peanut butter cups, and peanuts.