Preheat oven to 350F. Line two baking sheets with parchment paper and set aside. In a large bowl, combine cereal, almonds, pretzels, and oyster crackers. Set aside.
In a medium saucepan over medium heat, melt butter then add sugar, cinnamon, and agave, stirring 1-2 minutes until sugar is dissolved and slightly thickened.
Pour sugar mixture over snack mix and stir until coated. Spread snack mix in a single layer on prepared baking sheets and bake at 350F 20-25 minutes, stirring once halfway through.
Allow snack mix to cool completely then break into bite-sized chunks and stir in white chocolate and cranberries. Store in an air-tight container at room temperature. Enjoy!