Deus Ex: Human Revolution is the third game in the series and serves as a prequel to the original Deus Ex. The HR storyline unfolds in 2027, 25 years before the events described in the first Deus Ex. The game takes place across five megacities (including Detroit, Shanghai, and Montreal) around the globe. The main character, Adam Jensen, is an employee of the security service at Sarif Industries, a leading company in human body biomechanical operations. He survives an attack on the company’s office but is forced to agree to the implantation of special biochemical augmentations to stay alive.
The games in the Deus Ex franchise revolve around tactical gameplay that allows players to make critical decisions at any moment. HR includes four core gameplay styles - Combat (direct weapon attack), Stealth (sneaking and disabling opponents), Hacking (gaining information on hidden resources and controlling technology using special devices), and Social Skills (conversing and manipulating individuals for personal gain). Players can choose their preferred manner of behavior or switch between them at any point in the narrative. Furthermore, the behavioral options combine well with each other.
Unlike previous games in the series, Human Revolution features a regeneration model for health recovery. Such changes were made to ensure that players do not find themselves in a situation where they cannot continue the game and have to search for a medkit or food. The developers believe that a scenario where a player has to leave the game’s storyline to search for a medkit across the level is a negative development of events. They argue that the regeneration model encourages the development of tactical and strategic skills without requiring a departure from the narrative. Despite the new health recovery model, the game still has supplies of food used for the same purpose.
Another change in the game is the visual highlighting of objects with which the character can interact. This effect is explained as a modification of tactical vision. However, this highlighting of objects can be disabled if desired.