Assassin's Creed introduced the world to the ancient conflict between the Assassins and the Templars. Set in 1191 AD during the Third Crusade, the game follows Altaïr Ibn-La'Ahad, a master assassin tasked with eliminating nine key figures to restore peace to the Holy Land. The game was groundbreaking for its parkour movement system, allowing players to scale the towering architecture of Jerusalem, Acre, and Damascus with fluidity. It introduced the concept of "social stealth," where players could blend into crowds to avoid detection, a mechanic that became a staple of the series. The sci-fi framing involving the Animus device added a layer of mystery, connecting historical events to a modern-day conspiracy. It laid the foundation for a massive franchise, blending historical tourism with stealth-action gameplay.