Assassin's Creed: Brotherhood is a historical third person, stealth action-adventure video game developed by for Microsoft Windows, PlayStation 3 and Xbox 360. It was released for PlayStation 3 and Xbox 360 in November 2010, and is due for release on Microsoft Windows in March 2011.

Assassin's Creed: Brotherhood is a third person action-adventure video game with main emphasis on sandbox style gameplay in an open world of Italy. Like the previous installments, the gameplay's core mechanics are based on movements, crowd-blending stealth, assassinations and melee fighting system. The combat system features several improvements and for the first time in the series, the game offers a multiplayer mode alongside 40+ hours of single-player gameplay.

The game introduces a brand-new management system: the player can recruit new members by destroying any of nine "Borgia towers" around Rome where papal troops are stationed, then rescuing disgruntled citizens in their districts from harassing guards. The player, as Ezio, can then send them to assignments around Europe or call them for support during missions (if they are not already occupied). The assassin recruits are also able to provide arrow support for the player. Tasking the novice Assassins is essential to make them gain experience, and the player is able to customize their appearance, skills and weapon training by spending the skill points they've earned. Assassins can die on missions, from which they will not return. Ezio masters new gadgets, such as Leonardo da Vinci's parachute, which can be used when jumping from tall buildings, along with poison darts, a faster acting poison, a crossbow, and the ability to hold and throw heavier weapons like axes.

The player will have to rebuild Rome, which has fallen into ruin due to the corrupt rule of the Templars over the Papal States and concentrating all the wealth in the Vatican. Just like the town of Monteriggioni in Assassin's Creed II, the player will be able to invest in the city and witness its development and unlock rewards. The player will have to conquer and destroy Borgia towers to free city zones from the family's influence. Completing this unlocks new missions and opportunities. Rome is the biggest city ever created after the first two installments. Instead, a series of tunnel networks throughout the city allow the player to travel to different sectors of the city with ease. However players will be able to explore the entire city of Rome, visit a part of Naples, Spain and Monteriggioni.

The combat system has been upgraded to be faster and more dynamic. Striking first and offensive actions will be more deadly in Brotherhood than previous games where counter-attacks were the most efficient. Before, this made the player wait until the AI struck, which slowed down the pace of fighting. The AI in this game is thus more aggressive and enemies can attack simultaneously. To dispatch them, Ezio can use melee and ranged weapons at the same time, as well as introducing the hidden pistol in combat. After killing one enemy the player can start an execution streak to dispatch multiple enemies quickly. Ezio can throw axes and spears toward his enemies. There are new enemy archetypes in addition to those seen in Assassin's Creed II such as horsemen, arquebusiers, guards and others.

Horses play a larger role in Brotherhood, not only used as a means of transport (inside the city for the first time), but as a component of acrobatic sequences and advanced combat as well, allowing ranged weapons to be used while riding them. Brotherhood also introduces various types of horse-related assassinations, featuring horse-to-horse assassinations. There are environmental objects like the flower pot in Assassin's Creed II to move faster inside the city (a system of tunnels around the city allow fast travel), as well as new objects such as merchandise lifts to quickly climb up high buildings or structures.