Fallout: New Vegas takes place in an alternate timeline where a war over resources leads to a nuclear apocalypse. The game is set in the wastes of Nevada, surrounding the city of New Vegas, a gambling paradise untouched by nuclear devastation. A war brews between the NCR and various tribes, including the Great Khans and Caesar's Legionnaires. The NCR seeks to preserve ancient weaponry and bring law and order to the wastes, no matter the cost.
The player takes on the role of a courier who is tasked with delivering a package to Mr. House. However, once the package reaches its destination, a man in a checkered shirt and thugs intercept the courier, leading to a violent confrontation. The courier is shot, buried, and left for dead, but is later revived by a robot and sets out to uncover the identity of their would-be killers.
Gameplay resembles Fallout 3 , with an open-ended approach that focuses on exploration. Once character base stats are set, the game progresses in a non-linear fashion, allowing players to pursue main quests or explore the wastes and take up side-quests from various NPCs. The player will level up as they gain experience by completing quests, doing unique actions, and defeating foes.
There are new gameplay elements, including a variety of weaponry, aiming down sights with guns, and crafting unique items using workbenches, campfires, and reload benches. An influence system determines the protagonist's standing with various towns and factions, while trying to fool enemy factions requires stealth and careful disguise.
Fallout: New Vegas features a "Hardcore" mode, which introduces survival mechanics such as managing hunger, thirst, sleep, and radiation sickness. Ammo adds weight and can be cumbersome, companions can be killed in battle, and the protagonist's health will deteriorate over time if not managed properly.
The game also features traditional first-person combat using V.A.T.S. or action combat with a third-person camera option. The player can level up, gain perks (every other level), and use functions like fast traveling, waiting, sleeping, and adjusting the time of day to progress through the game.