Put all 9 cups of the cereal in a large bowl. In small microwavable bowl, melt chocolate chips, peanut butter and butter for 1 minute to 1 minute 30 seconds in the microwave until creamy and smooth. Pour peanut butter mixture over cereal, stirring until evenly coated.
Place 1/2 of the cereal mixture in 1-gallon food-storage plastic bag. Add powdered sugar. Seal bag; shake until well coated. Spread onto half of a waxed paper covered tray.
Stir M&Ms and sprinkles into remaining cereal mixture. Spread on the other half of the pan and put in the freezer for about 10 minutes.
Remove from freezer and mix both cereal mixtures into a serving bowl. Store in airtight container.