Recently, CDPR quest designer Philipp Weber shared insights into the development challenges and classic bugs of The Witcher 3's NPC simulation system in an interview with Edge magazine. Weber noted that players are eager to test the world's authenticity; even in a village with only eight houses, they carefully observe whether residents are dynamic living beings or static props. This high demand for detail once gave the development team quite a headache.
Today, thanks to mature pipelines, a small village can be built in just two hours. However, during development back then, the team focused on simulating NPCs' day-night routines, neglecting the logic for how characters respond to player actions, which resulted in many immersion-breaking bugs.
In early versions, NPCs had a uniform setting: upon seeing the player draw a weapon or engage in combat, they would drop whatever they were holding and scatter in panic. The system failed to distinguish between held items and infants. For weeks, female NPCs holding babies would drop them on the ground when faced with danger, severely breaking immersion. The team later fixed this issue by redefining behavior priorities.
The developers did not assign fixed patrol routes to NPCs. Instead, they placed numerous points of interest across the map, allowing characters to navigate autonomously and switch behaviors randomly. For example, in Novigrad's port, 50 sailors were paired with 200 activity points to prevent large groups of NPCs from clustering or repeating actions, giving the town a more lively atmosphere.
Previously, CDPR compared manually crafted NPCs with AI-generated characters, finding a significant gap in completeness and realism between the two. The meticulous design of pedestrians in Cyberpunk 2077 further confirms that carefully crafted minor interactions are key to shaping an immersive world.