Apocalyptic writing is usually dualistic in that two opposing supernatural powers, God and Satan, do battle; Demon and Angels fighting in a war. To save the day, apocalyptic writing included a promise that God would intervene in human history, destroy evil and bring the troubles of his people to an end. Apocalyptic focused on a period of time in the future when God would intervene to judge the world and establish rightousness.

How it's used in the Bible