The God-Killers are five weapons said to have been forged to fight the Faceless Ones. They are a sword, a dagger, a spear, a bow, and the Sceptre of the Ancients. The sword is wielded by Mevolent in the alternate universe in Kingdom of the Wicked . The Sceptre is the most powerful of the five weapons. The God-Killers are the main focus of The Maleficent Seven.
Tanith Low, who heard rumours of four weapons that could kill Gods, interrogates Jerry Ordain, a Sensitive who she believed could help her find the weapons and destroy them, to prevent them from killing Darquesse. She killed him after extracting what little she could and proceeded to hunt them down.
As part of her research, Tanith learned that Christophe Nocturnal had intel on one of the God-Killers. She later killed him after she extracted the intel.
It is revealed that Mevolent owned the sword in the alternate dimension. Valkyrie Cain saw it in a case in his palace. Much later, Mevolent carried it into battle and used it in Ratoath, in an attempt to destroy the last of the Resistance. He uses it in his battle with Darquesse. He briefly lost it and Darquesse took possession, killing several soldiers with it. She decides, however, that "swords aren't her thing" and throws it through a window. Mevolent presumably retrieved it afterwards.
Tanith assembles a team of seven criminals to hunt down the four remaining weapons . Meanwhile Dexter Vex assembles his own team of sorcerers to obtain the weapons, without the express permission of the Irish Council. The God-Killers were all in the hands of private collectors and Sanctuaries. Following a tense globe-trot, Tanith's team managed to obtain them all despite Vex's best efforts. Tanith sent Billy-Ray Sanguine to destroy them, but he instead had Sabine make forgeries so he could protect Tanith.
It is shown that Billy-Ray Sanguine gifted the sword, bow and spear to the Irish sanctuary. They are then used by Skulduggery, Erskine Ravel and Saracen Rue to fight against Darquesse. Sanguine keeps the dagger and uses it to save Tanith Low from the Black Cleaver
They were once regular weapons until they were dipped into a pool in the caves beneath Gordon Edgley's house this same pool is used to boost Stephanie (Valkyrie Cain's reflection) magical properties so Darquesse can use her body
- Only the Sceptre and the Sword have been seen with a duplicate in the alternate dimension. Presumably, the other three weapons have counterparts as well.
- Since Crab was a reclusive hermit, it is possible that he remained undetected in the alternate dimension and kept the Spear safe.
- Mevolent possessed the sword in the alternate dimension, possibly because he conquered the British Sanctuary.
- Erskine Ravel mentions that there are other God-Killer Weapons, if one were to believe the legends.
They appear or are mentioned in every book in the series.