It enhances the series by adding more content. Simple as that. More stories mean more gameplay time and more things to discover about the Arkham world.
One possible aspect of a Batman and Harley fanfic in the Arkham universe could be their complex relationship. Batman is always trying to uphold justice, while Harley is often caught between her love for the Joker and her own sense of right and wrong. In a fanfic, the author might explore how Batman could potentially save Harley from her self - destructive path. For example, Batman could use his detective skills to show Harley the truth about the Joker's abuse towards her.
One of the best moments could be when Batman manages to outwit Harley in a battle of wits. He uses his knowledge of her psychology to predict her moves. For instance, if Harley tries to set a trap using her knowledge of Arkham's layout, Batman quickly figures it out and turns the tables on her.
One possible fanfic could be centered around Batman's encounters with Poison Ivy within the Arkham universe. Maybe it could explore their complex relationship, with Batman constantly trying to stop Ivy's environmental extremism while also seeing the good in her intentions at times. For example, Ivy might be trying to protect a particular area in Arkham City that she believes is crucial for nature, and Batman has to find a way to balance the law and her motives.
It's an action-adventure game that shows Batman's early years. He faces off against various villains in Gotham City while trying to establish his reputation as a crime fighter.
It contributes by expanding the lore of the Arkham series. The Gotham City stories introduce new characters and scenarios that are related to the overarching theme of Batman's fight against crime in Gotham. This enriches the experience for players who are already fans of the series and also attracts new players who are interested in the Batman universe.
In many fanfictions, Jason saving Batman in 'Batman Arkham Knight' often shows a new side of their complex relationship. It could be a moment of redemption for Jason. Maybe he realizes the true meaning of Batman's mission and decides to put aside their differences. This scenario allows for deep character exploration.
One interesting aspect is the expansion of the Arkham City universe. It allows players to delve deeper into the lore and characters. For example, we get to see more of the relationships between Batman and his rogues gallery. Also, the stories often introduce new challenges and puzzles for Batman to overcome, which adds to the overall gameplay experience.
One popular theme is Batman's struggle against the chaos created by the villains. The Arkham games are known for their great villain portrayals, and fanfics often expand on that. Another theme is Batman's moral code and how he upholds it in the difficult situations within Arkham.