Place 4 cups of Chex cereal in a large bowl. In a microwave-safe bowl, combine 1 cup purple Candy Melts, ¼ cup peanut butter and ½ Tbsp vegetable oil. Microwave on HIGH for 30 seconds, stir and cook in 15-second intervals until smooth.
Pour melted peanut butter mixture over cereal, toss to coat. Pour coated cereal into a gallon ziplock bag. Pour a third of the powdered sugar (¾ cup) into the ziplock bag and seal. Shake to coat cereal. Add purple sugar and shake to coat. Pour coated cereal onto parchment or wax paper and allow to set.
Repeat the process with the remaining ingredients and green and yellow candy melts and colored sugar.
