In Assassin's Creed, Altaïr Ibn-La'Ahad uses a Hidden Blade as his signature weapon.
The Hidden Blade is a spring-loaded wrist weapon carried by members of the Assassin Brotherhood. It can be concealed beneath a sleeve and extended quickly, making it central to the series' stealth-focused combat and assassination missions.
Altaïr is the protagonist of the first Assassin's Creed game, released in 2007. His version of the weapon is associated with the Levantine Assassins during the Third Crusade. Later games show that the design changes over time, adding features such as poison mechanisms, detachable blades, and improved protection for the user's hand.
The Hidden Blade is sometimes confused with the Phantom Blade from Assassin's Creed Unity. The Phantom Blade is a later ranged weapon, while the Hidden Blade remains the franchise's iconic close-range Assassin tool.