Demon-Killing Knife

This knife, which originally belonged to Ruby but has passed to Sam and Dean, is capable of killing demons. This is something which previously only the Colt could do. The knife's blade is inscribed with symbols. The weapon's origin is unclear. While the Horsemen cannot be killed, this knife can damage them; it is used to cut-off the fingers of War and Pestilence.^{5.02 Good God Y'All,5.21 Two Minutes To Midnight}

Alastair, mysteriously, is resistant to the knife. It is unknown if Azazel and Lilith are as well, as both appear to be more powerful than him.

Name	Ruby's Knife
Manufacturer	Unknown
Powers	Can kill Demons; although Alastair is highly resistant to this Knife. This Knife can also damage/harm War Famine and Pestilence
Location/Owners	Most angels carry this weapon
Episodes	First Appearance: First Appearance: 3.01 The Magnificent Seven Last Appearance: 5.21 Two Minutes To Midnight

Ruby with her demon-killing knife in 3.01 The Magnificent Seven.

3.01 The Magnificent Seven

Ruby appears during the battle with the Seven Deadly Sins, and kills three of the demons with a dagger. Until this point, the only ways of getting rid of a demon had been exorcism, which sent it back to Hell, or with the Colt, which killed it.

Bobby states that he has never heard of a blade that could kill demons.

3.09 Malleus Maleficarum

Ruby tries to use the knife to kill Tammi but loses it in the ensuing fight. Dean eventually kills Tammi with it.

3.16 No Rest For The Wicked

Dean steals the knife in the hope of using it against Lilith. However, when Sam attacks her with it, she stops him with her powers. Later, after Dean has been killed, Sam is able to withstand her power, and she vacates the body she is using to escape Sam's attack with the knife.

4.01 Lazarus Rising

Dean stabs Castiel with the knife, but it has no effect on him.

4.09 I Know What You Did Last Summer

File:Rubysknife.jpg

Detail of the engraving on Ruby's Knife.

Sam stabs Alastair with the knife, but it appears to have no effect on him. While escaping from Alastair they lose the knife.

4.10 Heaven And Hell

Alastair uses the knife to torture Ruby. He says to her "This knife of yours... It's an exquisite piece. You must tell me where you found it." Eventually Sam and Dean get the knife back from Alastair.

4.16 On The Head Of A Pin

Alastair beats Dean unconscious after being freed from the devil's trap. Castiel arrives and throws the demon-killing knife into his shoulder. Castiel twists the knife with his powers, but Alastair manages to pull it out and lunges at the angel. Alastair attempts to send Castiel back to Heaven, but is interrupted by Sam.

4.22 Lucifer Rising

Castiel uses the knife to cut his arm so that he can use his blood to draw the Angel Banishing Sigil and temporarily get rid of Zachariah. Castiel gives the knife to Dean before sending him to St. Mary's Convent to stop Sam from killing Lilith. While he cannot prevent the breaking of the final seal - Lilith's death - Dean uses the knife to kill Ruby, who is revealed to have manipulated Sam and his abilities so that Lucifer could be freed.

5.01 Sympathy For The Devil

Meg orders the possessed Bobby to kill Dean with Ruby's Knife, but just as he is about to strike, Bobby manages to battle the demon possessing him and stab himself in the abdomen instead. The stab wound Bobby inflicted on himself with Ruby's Knife led to his inability to walk.

5.02 Good God Y'All

Dean and Sam go for supplies, and while Sam is getting salt from a store, two teenagers with black eyes enter. Sam kills them with Ruby's knife.

5.12 Swap Meat

Dean tries to use the knife on the possessed Nora.

Sam with the knife in 5.20 The Devil You Know.

5.14 My Bloody Valentine

Sam follows a demon into an alley and attacks him with Ruby's Knife.

5.20 The Devil You Know

Sam uses the knife to try to kill Crowley - and slices into the Impala's rear seat when the demon disappears. He makes another attempt, but is again unsuccessful. Later, Dean takes the knife and uses it to kill a demon protecting Brady. Sam eventually uses the knife to kill Brady.

5.21 Two Minutes To Midnight

Sam carries the knife while searching for Pestilence with Dean. Castiel than uses it to chop off Pestilence's finger to obtain his Ring. Later at the Niveus factory, Bobby kills two demons with it.

Links

• Ruby's Knife as reproduced by gembat
• Ruby's Knife as reproduced by angelicfoodcake