Some say that lying non-player characters can motivate player characters, at the cost of paranoia. Some say that characters in crime fiction may be justified in their dishonesty. Marvel comic books are full of liars. Psychology experts have advice for you about how to spot liars. Some recent research has addressed factors associated with designing video games with falsehoods. A relevant previous Ask.

About the "research" link: "Lying and deception are important parts of social interaction; when applied to storytelling mediums such as video games, such elements can add complexity and intrigue. We developed a game, "AlphaBetaCity", in which non-playable characters (NPCs) made various false statements, and used this game to investigate perceptions of deceptive behaviour. We used a mix of human-written dialogue incorporating deliberate falsehoods and LLM-written scripts with (human-approved) hallucinated responses. The degree of falsehoods varied between believable but untrue statements to outright fabrications. 29 participants played the game and were interviewed about their experiences. Participants discussed methods for developing trust and gauging NPC truthfulness. Whereas perceived intentional false statements were often attributed towards narrative and gameplay effects, seemingly unintentional false statements generally mismatched participants' mental models and lacked inherent meaning. We discuss how the perception of intentionality, the audience demographic, and the desire for meaning are major considerations when designing video games with falsehoods." Yin, M., Wang, E., Ng, C., & Xiao, R. (2024, May). Lies, Deceit, and Hallucinations: Player Perception and Expectations Regarding Trust and Deception in Games. In Proceedings of the CHI Conference on Human Factors in Computing Systems (pp. 1-15).