Melt butter, chocolate chips, and peanut butter together in a saucepan over medium-low heat, stirring until smooth, 5 to 10 minutes.
Mix peanuts, cereal, and raisins together in a large bowl. Pour chocolate mixture over peanut-cereal mixture; toss to coat.
Place 2 cups confectioners' sugar in a large covered container; add coated cereal mixture and remaining 2 cups confectioners' sugar. Cover the container and shake until cereal mixture is well coated with confectioners' sugar.