Add a subrule to rule “Insult Swordfighting”, called “High Seas Rules”:

If an insult swordfight is taking place at sea, the following must be adhered to:

* All insults must consist of exactly one sentence and must end with a word rhyming with ‘hated’, ‘died’, ‘vow’, ‘clay’, ‘knee’ or ‘you’.
* All responses must consist of exactly one sentence and must rhyme with the previous insult.
* Each insult (except the first one) must be preceded by a response to the previous insult (captains may not respond to their own insults).

Credit goes to Chivalrybean.