Black Knife Set is an Armor Set in Elden Ring. Black Knife Set is a special heavy armor used by assassins due to its stealth-enhancing materials. Sets of Armor in Elden Ring are composed of four armor pieces which are Helms, Chest Armor, Gauntlets, and Leg Armor.

• The Black Knife Armor can be altered to the Black Knife Armor (Altered) to remove the cape.
• The chest armor piece of this set muffles the sound of the wearer's footsteps, similar to the effect of the Crepus's Vial talisman and the Assassin's Approach incantation. The chest armor piece needs to be unaltered, with the cape intact, to receive this bonus. The cape only adds 0.2 weight, so leaving it on is highly advised. This silence effect also affects the wearer's rolls and jumps.
• The chest piece comes with an almost fully transparent cloak, including a hood.
  • The hood is worn over the following helms and other headwear:
    • Black Knife Hood
    • Bloodsoaked Mask
    • Astrologer Hood
    • Perfumer Hood
    • Chain Coif
    • Fingerprint Helm
    • Eccentrics Hood (Altered)
    • Nox Swordstress Crown (Altered)
    • Nox Monk Hood (Altered)
• Poise updated to patch 1.07. See Patch Notes for details.