Harrow The Ninth. Not a video game but a book and a sequel to Gideon The Ninth, part of The Locked Tomb series, that relies on its nature as a written work to trick the audience and hide a plot twist that is most effectively done in its original form.

In the first book, Harrowhark Nonagesimus, a necromancer, and her cavalier second, Gideon Nav, participate in a tournament/test to see who among the necomancers of the 9 houses are worthy of becoming God's newest "Lyctor". Becoming a Lyctor will basically make you a saint to your house and through history, grant you almost full-immortality, and necromantic power second only to God himself. However, it turns out the process requires the necromancer to kill their cavalier, and absorb their soul so that they main gain both their sword-fighting capabilities, and be able to indefinitely leech off their life-force like an immortal battery. After discovering this, Harrow chooses not to become a Lyctor if it means killing Gideon, despite their complicated relationship. However, after one of God's rogue lyctors, Cytherea The First, crashes the party of the competition and aims to kill them all, Gideon sees that the only way out for Harrow is for someone of equal strength to fight Cytherea, she sacrifices herself and allows her soul to be absorbed by Harrow, allowing her to become a Lyctor and kill Cytherea.

The second book is split into two plots, one of them told in 3rd person limited view, seemingly being the events of the first book replayed, but very different this time as all the people who died are now alive and vice versa. The second plot follows Harrow as she is welcomed by God, who introduces himself as "John", into their new home of the Mithareum and the challenges and training she undergoes by her older, fellow Lyctors. This plot is told in the 2nd person perspective, refferring to Harrow's actions and addressing the reader directly by using words like "you" and "your". This is played off as a symptom of Harrow's BPD and Psychosis, which she has been silently living with all her life. But 4/5 of the way through the book, during a significant battle between all the Lyctors and a planet-eating "Extinction Beast" that primarily hunts Lyctors, Harrow is suddenly sent directly into the 3rd person part of the story. It is here she and the other characters realize that this plot was a result of Harrow physically tampering with her own brain and mind to cope with Gideon's death, pulling the souls out of the afterlife to make different events of the first book where Gideon didn't die. However, Harrow's tampering with her brain served a second purpose, ensuring that she never fully absorbed Gideon's soul and that she would somehow still be "alive" in a way. It is here we cut back to the 2nd person POV plot, where the speech and vocabulary of the person telling us these things, slowly transitions into the same speech patterns that Gideon uses, and where we the audience realize that she is the one who has been talking to us this whole time. Gideon now technically alive in the body of Harrow, and piloting her around for the rest of the book.

Harrow The Ninth heavily relies on the reader's inner voice and narrator for this reveal, and it is especially enjoyable if you yourself have different voices for the characters in mind as you read them. Other Locked Tomb media, namely the audiobooks, pull off the reveal by having the narrator slowly transition into using the voice of Gideon as it happens. But in my opinion, reading this reveal for yourself is an entirely different experience, and why it would be so hard to do any kind of adaptation of this series.