In a large microwave-safe bowl, microwave caramels, water and 1/2 cup peanut butter on high for 1 minute; stir. Microwave for 1-2 minutes longer or until melted.
Add cereal and peanuts and stir until coated.
Spread in a greased 9x13-inch pan; set aside.
In another microwave-safe bowl, melt chocolate chips, butter and remaining peanut butter on high for 1-2 minutes and stir until smooth. Spread over cereal mixture.