10 Times Video Games Secretly Spoiled Their Own Story
10. Scanning Joker In Detective Mode Reveals He's An Impostor - Batman: Arkham City
Batman: Arkham City's climactic plot twist reveals that The Joker the player has encountered throughout the game actually isn't the Clown Prince of Crime at all, but Clayface, who has been masquerading as a healthy Joker while the real one is terminally ill and pulling the strings from the shadows.
It's a fantastic twist that most players didn't see coming, even if they perhaps sensed that something was a little off with the game's version of the villian.
But the truth was pretty much spelled out earlier on, as anyone who used Detective Mode during the Funhouse Joker boss fight would see that he didn't have a skeleton, and therefore wasn't human.
Furthermore, anyone who used Detective Mode on Clayface when he impersonated Commissioner Gordon in Arkham Asylum would be well aware of what The Joker's lack of skeleton specifically implied.
This is certainly one of those twists that seems decidedly more obvious on a second playthrough, but if you were savvy enough to scan The Joker early on, you'd know what was up long before the game finally played straight with you.