Place Chex cereal in a large bowl. Set aside.
In a medium bowl, microwave chocolate chips, peanut butter, and butter for 45 seconds remove from microwave and stir. Return to microwave for 25 seconds and remove and stir again. If still not melted, repeat process, lowering the number of seconds each time.
Stir in vanilla extract once the mixture is smooth.
Combine chocolate mixture with Chex cereal. Gently stir until evenly coated.
In a gallon Zipoc bag, combine cereal and powdered sugar; mix until well coated.
Add candy corn, sprinkles, M&M's, and bones.
Store in an airtight container for up to 5 days.