In "The Cask of Amontillado," there are two conflicts upon which the plot hinges: the conflict, or problem, of Montesor against Fortunato as he tricks the connossieur of wine to enter his family tombs in order to task the Amontillado, and the efforts of Montesor "to not only punish, but punish with impunity." That is, Montesor feels he must deceive Fortunato, yet later allow him to understand what act of vengeance has been committed against him.
To accomplish these almost contradictory tasks, Montesor urges Fortunato to drink, then he urges him to turn back as the tomb becomes damper, feigning his concern in order to deceive him. While so doing, Montesor hints at his vengeful act, stating that he is a "mason," using a pun upon the word, that Fortunato will realize only when it is too late and he is walled in. As Fortunato is walled in, Montesor repeats Fortunato's plea with mock irony: "Yes,...for the love of God."
However, Montesor does not receive a reply as he wishes:
But to these words I hearned in vain for a reply....No answer...No answer still.
Montesor complains that his "heart grew sick," but makes the excuse "on account of the dampness of the catacombs." Perhaps, then, only one conflict is resolved. The acknowledgement of Montesor's insidious plan has not been given by Fortunato.
A man wants to commit a murder but he doesn't want to get caught and punished. That is the main conflict. In any story of this type the conflict would be man against man. Montresor has to commit the murder in such a way that no one will suspect him, including the police and the victim's relatives. The conflict is not resolved until Montresor has succeeded in chaining Fortunato to the granite wall and sealing the entrance to the niche. Thus there is a conflict from beginning to end, as there should be in a short story. Certain problems add to the conflict as the story progresses. Montresor discovers that Fortunato is wearing the most conspicuous sort of a costume on the public streets crowded with people. Fortunato is even wearing a cap with bells that ring with every step he takes. Yet Montresor must not be recognized as the man with him on the last night Fortunato was ever seen alive. Montresor has to plan for the future as well as the present. He has to steer a boisterous, drunken man to his underground vaults an keep him manageable and unsuspecting up to the very moment he locks the padlock. (This is undoubtedly an old-fashioned padlock that locks with a key and not the kind that snaps shut automatically. A more modern padlock, such as we are familiar with today,would be easier to pry open.) What Montresor is accomplishing is extremely difficult, and it is sufficient for one short story without any additional kinds of conflicts. He not only commits his crime but avoids suspicion. He has committed the perfect crime. One of the biggest problems (conflicts) in committing a murder is disposing of the body. Poe has solved that problem by having Montresor commit the murder in such a way that the body is disposed of at the same time. In fact, Montresor disposes of the body before the victim is even dead.
The central conflict in the story is between Montresor and Fortunato. Montresor tells the reader that Fortunato has committed a thousand offenses against him. He does not name any of them, but they are serious enough to warrant a special type of revenge.
The other conflict concerns Montresor's revenge. Montresor must exact a special type of revenge for himself and for his ancestors. Fortunato must know that he is being punished for his offenses against Montresor as he is being killed. Only this type of justice will satisfy Montresor's revenge.
Montresor must take revenge on Fortunato to restore honor to his family name and allow his ancestors to return to their restful slumber in the afterlife.