Deus Ex: Human Revolution is an action role-playing game with incorporated first-person shooter and stealth mechanics. Players take the role of Adam Jensen, a man equipped with mechanical cybernetic implants called augmentations. The game's environments, ranging from open world hubs to more scripted environments, are explored in first-person, although actions such as hiding behind cover, conversing with non-playable characters (NPCs), and some attack animations switch to a third-person view. In these environments, players can find NPCs that will advance both the main story quest and optional side quests: completing quests, along with other actions such as combat with enemies, rewards Adam with experience points, which raise his experience level. Also accessible are black market vendors which supply equipment and weapons for Credits, the in-game currency. Interactive objects within environments can be highlighted, although these options are either turned off on the hardest difficulty or can be turned off in the options menu by the player.
There are a variety of ways to approach the game's situations: players can use a violent approach and shoot their way through environments while using cover to hide from enemy fire. Alternately, Adam can take a stealthy approach, avoiding guards and security devices, again using cover to avoid enemy sight lines. Adam can move between covers, and move around corners while staying hidden. Taking down enemies while in stealth mode also has lethal and non-lethal melee options, in addition to weapons that can both kill and stun enemies. Adam can also move the bodies of enemies into hiding places, preventing them from being seen and raising an alarm. A key part of Adam's abilities are augmentations, which can be acquired and upgraded using Praxis Kits either bought from special vendors, found in the game environments, or are automatically unlocked by leveling up: higher-level augmentations require more Praxis Kits to unlock. Augmentation functions can range from passive enhancements to Adam's vision or damage resistance, to active upgrades such as allowing Adam to fall from great heights without being injured or increase his strength. Some augmentations are dependent on Adam's energy level, deactivating after an amount of energy has been drained.
At multiple points within the game, Adam partakes in conversations with NPCs related to main and side quests. When talking, Adam is presented with three different conversation options that affect the outcome of conversations: choosing the right option can help with completing objectives while choosing the wrong option closes off that route and forces the player to find an alternate solution. A "Social" augmentation enables better reading of an NPC's expression and judging their psychological profile, improving chances of selecting the right dialogue option. While in the game's environments, Adam finds terminals and computers that can be accessed either with a password or through hacking. When hacking, the hacking screen is summoned, which shows the pathway through a device's security system to access the information: the pathway is accessed by opening "directory" nodes to reach the registry. Different nodes have different ratings, affecting how easily they can be accessed. Various devices have different grades of difficulty, which in turn dictate how many times hacking may be attempted. Each hacking attempt activates a Diagnostic Sub-Routine which works to stop the hack, activating a time limit once it is alerted. Adam can use additional skills and items to lengthen the time, such as software to stop or instantly capture nodes or fortify captured nodes to increase the time limit. Successful hacks yield experience points, Credits, and sometimes additional items.
This article uses material from the Wikipedia article Deus Ex: Human Revolution, https://en.wikipedia.org/wiki/Deus_Ex:_Human_Revolution, which is released under the Creative Commons Attribution-Share-Alike License 3.0, https://creativecommons.org/licenses/by-sa/3.0/.