Can you smoke 9 year old Montecristo Cigars

[Prospector]

That long outside of a humidor means they're likely all dried out. I wouldn't even consider trying to smoke them until they are re-humidified, and even then don't know how the taste might be affected by the ordeal. If you want to try re-humidifying them I would give them at least a month at 65 to 70 % humidity before attempting to light one up. I'm no expert on this - only hypothesizing.