In "The Masque of the Red Death," the protagonist is the Prince and the antagonist is the Red Death. However, since this story is an allegory, Prince Prospero is symbolic as the pestilence of the "red death." The Prince is symbolic of health, happiness, and prosperity. Yet, even possessing these qualities, the Prince has no defense against the inevitability of death.
Deluded that he does, he invites courtiers to his castellated abbeys whose "walls have gates of iron." Gathered inside these walls are "musicians, buffoons, ballet dancers, Beauty, and wine." There is a grand gathering for a masquerade. However, death masquerades itself and enters this fortress, passing through seven rooms--much like Shakespeare's seven stages of man--and conquers the Prince himself who has "rushed through the six rooms" in order to encounter the Red Death as he retreats. However, suddenly the Death turns toward the Prince. A cry is heard and the Prince lies prostrate in death.
When the guests hear this cry, they summon "wild courage of despair" and rush into the room painted with black
And now was acknowledged the presence of the Red Death. He had come like a thief in the night. And one by one dropped the revelers...and died each in the despairing posture of his fall...And Darkness and Decay and the Red Death held illimitable dominion over all.
In literature, a protagonist is the story's leading character. An antagonist is the person or thing that opposes the protagonist and causes conflict throughout the story. As was mentioned in the previous post, the protagonist in the short story is Prince Prospero, and the antagonist is the "Red Death." Throughout the short story, Prince Prospero invites a group of aristocrats to isolate themselves inside his abbey to avoid the fatal contagion that is sweeping through the countryside. The pestilence is known as the "Red Death," and it kills its victims within a half hour of their becoming infected with the disease. Prince Prospero is determined to escape the "Red Death" and hosts a ball while the plague claims the lives of thousands outside of the abbey's walls. Unfortunately, Prince Prospero is not able to cheat death, as a mysterious individual that personifies the "Red Death" kills him and all of the guests inside the castle. Since the "Red Death" causes conflict throughout the story and directly opposes Prince Prospero, it would be considered the antagonist.