A Kris Knife in Fighting Fantasy is usually forged of silver tempered and shaped in the eternal hellfires themselves. It is used by Demon worshippers as a ceremonial instrument. The blade's unearthly origins endow it with exceptional properties, and indeed it is perhaps most valued for being the only weapon capable of slaying a Hell Demon.
In combat, the Kris Knife in House of Hell was capable of bestowing +3 skill points to its wielder against humans close in favor with the house's Master, and +6 skill points against the Master himself. The Kris in Eye of the Dragon weakened the encountered Hell Demon by 2 skill and 4 stamina points of damage per hit.
- In the gamebook House of Hell, the knife is described as having a pearl handle.
- In Eye of the Dragon, Littlebig mentions that a Kris Knife is the only blade capable of piercing the skin of lesser Demons. In this, at any rate, he is mistaken, as it seems that only Hell Demons have an exclusive vulnerability to Kris Knives - for other lesser Demons, normal weapons or magical swords seem to suffice.