From Monkey Island wiki
Insult swordfighting is an activity within the Monkey Island games, most prominently featured in the first and third games. Insult Swordfighting differs from regular swordfighting in that the participants are required to fling insults and counter-insults to one another.
In a regular fight one pirate presents an insult to which the opponent must present the appropriate counter insult. If a pirate can't produce the correct counter-insult he loses a round. After losing three rounds he will lose the match. If the opponent responds with the correct counter-insult, he wins the round and is allowed to present his own insult.
In each game which features insult swordfighting the player must fight a final boss-fight of sorts in which he is only allowed to respond and must use the counter-insults to respond to a completely unique set of insults. Also, in the first and third game this fight always lasts longer than three rounds.
Insult Swordfighting was originally intended as a parody of old Hollywood swordfights, such as those in Douglas Fairbanks pictures, where the dueling fighters would spend as much time flinging insults at each other as swinging their swords. As LucasArts designer Noah Falstein puts it:
...when Ron was talking to me about Monkey Island he casually remarked that he’d realized that the boxing interface would make a great sword-fighting interface for his new game. I confessed to the history of the concept, and for a while we were stumped. Then I suggested that some of the best classic swordplay in movies involved more talking than fighting — thinking of old [Errol Flynn movies or the then-recent film The Princess Bride. That seemed more appropriate anyway for the comic tone of his game. What if sword-fighting in Monkey Island was about insult and rejoinder, not thrust and parry? And so out of movies, a classic game mechanism was born that proved to be one of the more popular parts of Monkey Island.<cite_reference_link>
Insult swordfighting makes up a huge part of the first Part of the game. The player must challenge and defeat Carla the Sword Master in insult swordfighting. After buying a sword from the Storekeeper the player is trained by Captain Smirk, who gives Guybrush a few starter insults. Going around the island the player must face various rank of pirate before eventually gathering a sufficient amount of counter-insults.
When facing Carla, she uses her own unique set of insults (which the player can use to win swordfights on his own as no pirate knows the counter-insults). The player is only allowed to respond, meaning that the learning of counter-insults is more vital for the game's completion.
All of the insults for the game were written by author Orson Scott Card.<cite_reference_link>
You Fight Like A Dairy Farmer
The most famous and often repeated of the insults and counter-insults from the first game are "You fight like a dairy farmer" and "How appropriate, you fight like a cow". The line has become a running-gag within the series as well as in the Monkey Island fan community. A behind the scenes video from the commentary recording sessions for Monkey Island 2 Special Edition: LeChuck's Revenge revealed that Orson Scott Card's son thought up the original line.
In the second game insult swordfighting is mentioned when Guybrush notes that "this game is a cinch" after facing Rum Rogers, Jr. who refuses to fight him (Rum then challenges him to a drinking contest).
In the third part of the game the player must challenge other pirate ships in ship-to-ship combat, after which the player must battle the captain of each ship in insult swordfighting. According to the rules of swordplay at sea the insults must rhyme, but otherwise the game mechanics are exactly the same as in the first game, with emphasis in learning new insults and counter-insults.
Eventually the player must face Captain René Rottingham, who, like Carla before him, uses his own unique set of insults, which the player must counter with the regular counter-insults. Also, Guybrush can provide a humourous alternative response to each insult, which will however lose him a round.
By the fourth game insult swordfighting has become a paradigm for a whole set of insult games. Insult swordfighting itself is featured in a joke-match against Ozzie Mandrill, which the player can't win. Instead, the game features a round of insult arm-wrestling against Ignatius Cheese, which the player has to win in order to convince him to become Guybrush's navigator. Unlike in previous games, there is no insult-collecting required and instead the player chooses his insults and responses from a set list provided by the game.
Instead Monkey Kombat supplements insult swordfighting as the game that must be learned and practised extensively before facing a boss.
Insult Swordfighting, while alluded to in earlier chapters, does not play any role until the final chapter (being replaced with 'Pirate Face-Off' in "Lair of the Leviathan"). In "Rise of the Pirate God", Guybrush swordfights both a ghostly swordmaster and a dejected Morgan LeFlay at the same time. In this variation, he has to select a counter that simultaneously insults the swordmaster and encourages Morgan. Many of the insults and comebacks are from the previous games.