Master-crafted Weapon
This upgrade can be applied to a weapon identifying it as an especially fine and well-engineered example of its type. Apart from Daemon weapons, any close combat weapon can be master-crafted. Only ranged weapons found in the Chaos Space Marine Armoury can be master-crafted. A master-crafted close combat weapon can re-roll one miss in each round of Close Combat. A ranged weapon can re-roll one miss each Shooting phase. A miss can only be re-rolled once.
Errata — Chapter Approved: Codex: Chaos Space Marines Q&A (v3.0): Only one weapon may be master-crafted per model — you cannot master-craft more than one weapon on the same model. Gifts of the Gods weapons that are not Daemon weapons (such as a chain axe, Plague Sword, or Axe of Khorne) cannot be master-crafted, since master-crafting is only available to weapons from the main Weapons list and the ranged weapons of the Armoury.