An ancient knife that was created by the Kurds which possesses the power to kill demons. Ruby obtained it by Season 3. It eventually passes into the possession of Sam and Dean Winchester, who use it as their most common means of killing demons.
At first glance, the knife appears to be an ordinary hunting knife with a curved, serrated-edged blade and a wooden handle. However, upon closer inspection, symbols can be seen engraved along the blade.
Powers and AbilitiesEdit
This knife is capable of killing most demons with a single stab to a vital area, such as the chest or the neck of the demons' vessels. As with The Colt, those killed by the knife briefly glow with orange light, which flickers out as the demon dies. Even non-lethal cuts are excruciatingly painful for demons in the same way that non-lethal cuts from angel blades are to angels.
The knife is also capable of harming the Horsemen War and Pestilence; it was used to cut their fingers off in the episodes they appeared in. It is also capable of killing Hellhounds. However, it is not capable of killing angels - aside from the damage to his vessel, Castiel was unaffected by the knife when Dean stabbed him during their first encounter. Its effect on other supernatural creatures are unknown, as it has never been used against anything else.
Very few demon types are immune to the demon-killing knife such as Alastair and the Knights of Hell. However, the knife was capable of inflicting pain on Alastair and the last surviving Knight Abaddon, in fact it was even able to temporarily incapacitate the latter for a few moments. The angels believed the knife could kill the demon Samhain, although he demonstrated an unusual resilience to the knife, finding cuts from it merely somewhat uncomfortable rather than agonizing like a normal demon. Even the first demon Lucifer created, Lilith, was wary of it, although whether a demon of her status is affected fatally by it is unknown.
- Series creator Eric Kripke originally wanted the knife's origins to remain unknown to retain an air of mystery.  When Sam asked where she got it, Ruby deflected the question with a joke. Alastair did not recognize it, remarking that it was a "magnificent piece" and telling Ruby "you must tell me where you found it." However, the Season 8 episode As Time Goes By finally revealed that it was forged long ago by the Kurdish people.
- Kripke refers to as "a hand-to-hand version of the Colt". 
- A deleted scene from "Frontierland" shows The Colt's creator, Samuel Colt, was in possession of the knife in the nineteenth century.
- Season 3
- Season 4
- Season 5
- Season 6
- Season 7
- Season 8
- Season 9
- ↑ Michael Ausiello (August 19, 2009). "Ask Ausiello: Spoilers on 'Grey's', 'House', 'NCIS', 'Bones', 'Gossip Girl', 'Supernatural', and more!". EW.com.
- ↑ Knight, Nicholas, (Season 3 Companion), p.22