The story often involves Two - Face creating chaos in Arkham City. He sets up elaborate schemes that are based on his idea of 'justice' which is warped by his split personality. Batman has to figure out how to stop him without causing more harm to the already chaotic Arkham City. This includes tracking Two - Face down in his various hideouts and dealing with the traps and henchmen he has set up along the way. It also delves into the backstory of Two - Face, how he became the way he is, which gives more depth to his character and the overall story.
Probably. The Arkham series has a connected storyline, and it would make sense for the Arkham Knight new story to be a continuation. This way, it can keep the lore consistent and develop the characters further. For example, we might see how Batman has changed since the last encounter with his foes.
The main characters are Batman and Two - Face. Batman is the hero who tries to maintain order and justice in Arkham City. Two - Face is the villain with his split - personality causing trouble.
The Arkham Knight's origin story is quite complex. He was created as a military-trained antagonist to Batman. He has a vendetta against Batman, partly due to his own past experiences and the events that led him to become this highly skilled and vengeful figure. He was trained in combat and strategy, making him a formidable foe for Batman in the Arkham series.
Yes, there are many Arkham Knight fanfics that are suitable for general audiences. You can find them on various fanfic websites by using filters or search terms like 'family - friendly Arkham Knight fanfic' or 'PG Arkham Knight fanfic'.