Whatt is the major conflict of this story?
There are two major conflicts that readers normally come away from reading Poe's "The Cask of Amontillado" with.
First, there is a definite internal conflict as seen by Montersor. Internal conflict is the conflict which happens within a character. Therefore, the main internal conflict is between Montresor and himself. Montresor cannot let go of the fact that Fortunato has inflicted "a thousand injuries" upon him.
Second, there is the external conflict between Fortunato and Montresor. Montresor does not like Fortunato because of the "thousand injuries." Therefore, he finds it necessary to murder him by walling him up in the catacombs.
One last conflict, not normally recognized, is the external conflict of nature against man. The catacombs contain air which is detrimental to the health of the men. Regardless, they go into the catacombs.
Choose any of the conflicts above to make your claim as to which is the major conflict presented in Poe's story.