Preheat oven to 350 degrees. Line two large baking sheets with parchment.
In a VERY large bowl (I used my cast iron Dutch oven, actually), combine the pretzels, goldfish, Cheez-its, Chex, butter, buffalo sauce, parsley, smoked paprika, garlic, onion, and dill. Season with salt and pepper, then toss until everything is thoroughly coated, about 2-3 minutes. I just used my hands to throw everything around.
Spread the snack mix on the two baking sheets in a single layer. Bake for 15-20 minutes, stirring once halfway through baking time, until crisped and golden. Let cool slightly, then serve, or cool completely and store for up to a week.