Wash your hands and clean your counter tops. Preheat oven to 250*F (or pellet smoker to 225*F).
Melt butter with olive oil in a small sauce pan. Add Worcestershire sauce, sugar, garlic powder, dried oregano, black pepper, parsley, and salt. Mix until well combined.
Add corn cereal squares, rice cereal squares, oyster crackers, bagel chips, and pretzels to a large bowl.
Add melted butter mixture to large bowl. Toss cereal mixture to coat.
Pour snack mix across a foil-lined cookie sheet.
Bake the snack mix for 1 hour, stirring every 15 minutes. (or 1 ½ hours in the pellet smoker, stirring every 15 minutes)