Measure cereal into a large bowl and set aside. Line a baking sheet with wax paper and set aside.
In a medium microwave-safe bowl, melt together the chocolate chips, peanut butter, and butter for 1 minute, then stir. Continue microwaving in 30-second intervals, stirring in between until smooth.
Pour the mixture over the cereal and gently mix until the cereal is all coated.
Transfer the mixture to a 2-gallon Ziploc bag and add the confectioner’s sugar. Seal the bag and shake until all the cereal is coated.
Spread the cereal out onto the baking sheet to cool. Sprinkle dark chocolate chips and M&M candies throughout the mixture.