Here's NCL luggage rules from their FAQ
How many suitcases can I bring?
Each person is allowed up to 200 pounds of personal luggage on board. However, if you are traveling by air, ask the airline if it has different restrictions. Airlines and NCL have limited liability for loss, so be sure all baggage and personal belongings are properly insured. Suitcases should be securely locked and tagged. You should hand-carry medication, jewelry or other valuables and important documents.
You're allowed 200 pounds per passenger.