Bring 1 cup sugar and 1 cup corn syrup to boil for 3 minutes over medium heat. Remove from heat and add 12 oz. crunchy peanut butter; stir until smooth. Add 3 cups rice crispies cereal and stir to coat.
Turn out into 9x13 inch greased pyrex and press into shape. While this sets, melt 1 cup chocolate chips and 1 cup butterscotch chips together in microwave; stir until smooth. Pour over cereal mixture and cut into squares when cool.