Place corn syrup and sugar into large saucepan. Cook over medium heat, stirring frequently until sugar dissolves and mixture begins to boil. Remove from heat. Stir in peanut butter; mix well. Add rice krispie cereal; stir until well coated. Press mixture into a greased 13x9x2-inch pan and set aside. Melt chocolate and butterscotch chips together in a small saucepan over low heat. Spread evenly over cereal mixture. Let stand until firm.