Set your slow cooker to LOW.In your slow cooker, add in the cereals, peanuts and pretzels.In a small bowl mix together the melted butter, seasoning salt, worchestershire and garlic powder. Pour over the cereals and nuts in the slow cooker and fold in to cover everything.Cook in your slow cooker for 3 hours, stirring every hour in the first 2 hours and twice in the last hour to prevent burning.Once done, lay out the mix on a cookie sheet to cool. Once completely cooled, you can store the remainder in a container at room temp.