Mix together cinnamon chex, wheat chex, vanilla chex, pecans, graham crackers, dried cranberries, pumpkin seeds together in the bowl of a large crock-pot.
Mix together butter, brown sugar, pumpkin pie spice and vanilla in a small bowl.
Pour butter mixture over the the cereal mixture and toss to coat.
Cook in crock pot on high for 2 hours. Stir mixture every 20 minutes.