The Hidden Blade is the Assassin order's traditional forearm weapon in Assassin's Creed.
The weapon is a retractable blade concealed beneath the user's sleeve. Assassins use it for close-range attacks, especially when approaching a target discreetly. Its design allows the blade to slide out from the bracer and retract when not in use.
In the original game, the weapon is associated with a ritual in which an Assassin sacrifices the ring finger to make room for the mechanism. Later games explain that this injury is not universally required, and technological changes make the traditional practice less central. Leonardo da Vinci also modifies Ezio's equipment in Assassin's Creed II.
The Hidden Blade should not be confused with the Phantom Blade from Unity, which is a ranged wrist-mounted weapon, or the Hookblade used by Ezio in Revelations. Different games add specialized variants, but the Hidden Blade remains the iconic signature weapon of the Assassin Brotherhood.