Is Marley from A Christmas Carol a flat or round character?

Marley is a flat character.

Marley, from the novel "A Christmas Carol" by Charles Dickens, is generally considered to be a flat character. Flat characters are ones that are not well-developed and have few distinguishing characteristics. In contrast, round characters are more complex and well-developed, with a variety of traits and motivations.

Marley is described as Scrooge's former business partner, who has died and come back as a ghost to warn Scrooge about the error of his ways. He is a relatively minor character in the story, and his primary function is to serve as a catalyst for Scrooge's transformation. As such, he does not have a lot of depth or development as a character. He is essentially a one-dimensional figure who exists to serve a specific purpose in the story.