Dump all the cereals into your large mixing bowl carefully. Add the mini pretzels and the mixed nuts to the bowl too. Stir the dry ingredients gently with your hands to combine them.

Put the salted butter into your small microwave safe bowl. Heat it for thirty seconds until it is fully liquid. Watch it closely so it does not pop or splatter inside.

Pour the Worcestershire sauce and hot sauce into the hot melted butter. Whisk in the garlic powder, onion powder, celery salt, and paprika. Blend the liquid until the spices are fully mixed.

Drizzle the spicy butter mixture over the large bowl of cereal. Stir the mix thoroughly with your wooden spoon for two minutes. Make sure every single piece gets a coat of the liquid.

Pour the coated snack mix onto your prepared baking sheet. Spread it out flat into a single, even layer. Do not let the ingredients pile up too high on the pan.

Place the baking sheet into the hot oven carefully. Bake the mix for one full hour to make it crunchy. You must stir the mix thoroughly every fifteen minutes so it cooks evenly.

Remove the hot pan from the oven using oven mitts. Let the snack mix cool completely on the baking sheet. The mix will become much crunchier as it sits on the counter.