How can a writer use/manipulate genre conventions for effect? (Genre conventions are themes, setting, characters, plotlines, narrative structure, mood, props or significant objects.)

A writer can use genre conventions to great effect by the inclusion of such conventions at strategic times in the plot when there is a climax or anti climax.

Explanation:

Some genre conventions can be used to maximize effect during strategic moments in a plot. Use of characterizations, plotlines, setting, props, etc can be used for effect during conflict resolution and denouement.

In a play, the character of a protagonist or antagonist can be used in climax to achieve great effect. For example, an antagonist can suddenly be portrayed to have a sudden change of ideology and do a certain thing that will make him capture the attention and sympathy of the audience.

The antagonist may have been portrayed as a heartless criminal who destroys all that stands in his way, but at the climax of the drama, his character can be portrayed to help an old woman cross a busy road, or beat up bullies that ganged up against a random child or even help the protagonist in a very unexpected manner.

This sudden change in the characterization of the antagonist, coupled with the mood of the audience in a setting has used the genre conventions to create effect.

the answer to this question is unstoppable.