Sweat System Controls Character Exertion
The system varies sweat output for protagonists Jason and Lucia or any other character depending on the intensity of their current action. Dancing vigorously in a nightclub causes greater perspiration than lighter movement, and harder workouts produce more visible sweat on Jason.
Trailer Glimpse and Studio Expansion

A brief scene of Lucia dancing in the August trailer shows a skin glisten consistent with the new sweat mechanics. Rockstar opened an additional Los Angeles studio staffed with writers, producers, and directors solely to populate the game with NPCs.
Detail Level Tied to Delays and Budget
The feature illustrates the unprecedented scope of realism that prompted multiple delays and the highest production spend of any title to date, though still under the reported $1.5 billion ceiling. Public statements about pursuing perfection align with the resources required for such systems.