The main key character is the player - controlled Big Daddy. He is unique in that he has a different perspective compared to the other characters. Dr. Steinman is also a key character. His experiments and his madness are part of what has made Rapture the way it is. And then there are the Alpha Series Big Daddies. They are predecessors to the main Big Daddy character and their existence and actions are intertwined with the overall story.
The Big Daddy is a key character. He is a large, imposing figure who protects the Little Sisters. The Little Sisters themselves are also important. They are these young girls with a special connection to the ADAM in Rapture. And of course, the protagonist, whose journey and actions drive much of the story forward.
In Bioshock Original Story, the player - controlled character is the main character who stumbles into Rapture. Andrew Ryan is a central figure. He is the one who built Rapture with his ideals of a free society, but his creation turned into a nightmare. The Little Sisters are key characters too. They are these young girls who are bound to the ADAM collection process. And the Big Daddies are their protectors. These hulking figures are a major obstacle and part of the unique ecosystem of Rapture. There are also other characters like Dr. Tenenbaum who play important roles in the overall story.
The main characters in the original Bioshock Infinite story are Booker and Elizabeth. Booker is a complex character with a troubled past. He's on a mission to rescue Elizabeth which sets the whole story in motion. Elizabeth, on the other hand, is a powerful young woman. She has the ability to open 'tears' in space - time. Comstock is another important character. He rules Columbia with an iron fist, his actions and ideology are at the center of the story's conflict.
Well, in the Bioshock Infinite original story, the city of Columbia is a major element. It has a hierarchical society with different classes. Elizabeth's powers play a crucial role too. She can open tears in space - time, which leads to many interesting plot developments. Also, the conflict between Booker and the ruling powers in Columbia, like Comstock, drives the story forward.
One of the key themes is the idea of alternate realities. The story dives deep into different versions of the world. Another theme is the concept of power and how it corrupts. Comstock, for example, is a character who is consumed by his thirst for power. Also, there's the theme of redemption, as Booker tries to make up for his past mistakes throughout the game.
Often, characters who are powerful yet morally ambiguous are popular. For instance, an OC who has the power to manipulate the Vigors but is not sure whether to use them for good or evil. They can be a sort of anti - hero, which always attracts readers.
There are two key characters in Bioshock Infinite's story. Booker DeWitt, a tough and somewhat jaded man, is the protagonist who embarks on the journey to Columbia. Then there's Elizabeth. She has been held captive in Columbia but she's far from helpless. Her powers related to the Tears in reality are fascinating. As the story progresses, their relationship evolves. They also encounter other characters such as the zealous Comstock, who rules Columbia with an iron fist and whose actions and beliefs drive much of the conflict in the story.
One of the main characters is often Jack, who finds himself in the strange world of Rapture. He has to navigate through the dangers and figure out what's going on.
I'm not entirely sure which specific characters are the main ones in the 'Bioshock the novel', but it's likely to include some sort of protagonist who ventures into Rapture and has to deal with the various threats there, like the Splicers and Big Daddies. There may also be some sort of antagonist representing the controlling or corrupt forces in the city.
Frank Castle, also known as The Punisher, is the central character. He is a vigilante driven by the need to avenge his family's death.
Tony is a key character. He is a former Jet and his relationship with Maria, a Shark's sister, is central to the story. Maria is also crucial as her love for Tony drives much of the plot. Then there are Riff, the leader of the Jets, and Bernardo, the leader of the Sharks.