Answer:
An unreliable narrator.
Step-by-step explanation:
Edgar Allen Poe's short story "The Cask of Amontillado" tells the story of one man's revenge upon his friend who he thinks have been insulting him too long. The story dwells on the revenge of Montresor on Fortunato.
The narrator or speaker of the story is Montresor but he has no credibility, telling the story only from his own point of view. This use of such kind of narrator by the writer heightens the level of uncertainty of the story and the sense of the horror felt by us, the readers. This unreliable narration through the character of Montresor makes the story doubtful, and thus making the readers' to be uncertain about their feelings about the story.