Add the Chex cereals, pretzels, bagel chips, cheese crackers, and mixed nuts to a very large bowl. Stir to combine, then set aside.
Mix the melted butter, ranch mix, and dried dill. Pour half of the butter mixture over the cereal mix and gently stir to coat. Add the remaining butter mixture and stir gently until everything is coated.
Split the snack mix between two rimmed half-sheet pans and spread evenly on the pan. Bake for 1 hour and 15 minutes, stirring every 15 minutes.
When done, cool completely, then store in an airtight container.