Ruby's knife — an ancient demon-killing knife of the Kurds
- Record Type
- Weapon
- Permanent Archive ID
- SPN-WPN-000019
- Aliases & Epithets
- Ruby's knife; Ruby's demon-killing knife; demon-killing knife; demon blade; demon knife
Ruby's demon-killing knife gave the Winchesters a way to kill most demons permanently, but every use carries rules and consequences. It usually kills the possessed vessel, fails against the strongest classes of demons, and cannot kill angels or Horsemen.
What Ruby’s knife actually does
Ruby arrives with something hunters had never seen before: a knife that can kill a demon instead of merely sending it back to Hell. A lethal strike kills most demons, but it usually kills the possessed person too. That cost is one reason Sam’s later ability to exorcise demons without killing their vessels matters so much.
The rule has limits
The knife is powerful, but it is not universal. It does not kill angels, Horsemen, Knights of Hell or Princes of Hell. Alastair survives repeated wounds. Abaddon is hurt but not killed. Cain stabs himself without injury, and Ramiel survives a direct attack. Threats involving Lilith, Crowley, Demon Dean and Amara never become clean immunity tests, so the page keeps those outcomes unresolved instead of pretending the show answered them.
From Ruby’s weapon to the Winchesters’ standard gear
The knife first appears in Season 3 and remains in use through Season 15. Ruby, Sam, Dean, Bobby, Meg, Linda Tran and several other characters carry or wield it. It kills ordinary demons and hellhounds, cuts the rings from Horsemen and becomes one of the clearest examples of how Supernatural builds rules through consequences: what a weapon can kill matters, but so does who may die with the monster.
Overview & Classification
- ID Number
- 19
- Type
- Ancient supernatural weapon / demon-killing knife
- Creator / Origin
- An ancient demon-killing knife of the Kurds; its individual maker and the circumstances under which Ruby obtained it are not identified on screen.
- Owners / Users
- Ruby; Sam Winchester; Dean Winchester; Bobby Singer; Meg; Becky Rosen; Jeffrey; Linda Tran; Gunnar Lawless; Luther Shrike. Additional brief wielders and handlers are recorded in the episode chronology.
- Targets
- Primarily demons; also used against hellhounds, Horsemen, an angel, a Knight of Hell, a Prince of Hell, humans and a creature encountered in Purgatory.
- Known Kills
- Numerous ordinary and crossroads demons, including Tammi and Ruby; hellhounds; and human Jeffrey. Bobby survived stabbing himself, but the wound left him paralyzed. A Purgatory creature identified in supporting reference material as a rugaru was also killed with it.
- Known Failures
- Castiel was unaffected beyond damage to his vessel; Alastair survived and resisted its killing power; Abaddon was hurt but not killed; Cain stabbed himself without injury; Ramiel survived. Attempts involving Lilith, Crowley, Demon Dean and Amara were interrupted, avoided or never completed, so they are not confirmed immunity tests.
Equipment, Objects & Places
- Weapon Name
- Demon-Killing Knife
- Related Artifact IDs
- No separate governed artifact is required. The knife is the canonical weapon entity; its symbols and antler-like handle remain attributes of this record.
Abilities, Rules & Limitations
- Powers / Properties
- A lethal stab to a vital area kills most demons and normally kills the possessed human vessel with them. Nonlethal contact causes severe pain to ordinary demons. The knife can kill hellhounds and can physically injure humans. It can cut the fingers from Horsemen so their rings can be removed, but it does not kill the Horsemen themselves.
- Limitations
- It does not kill angels, Knights of Hell or Princes of Hell. Powerful demons may resist or survive it: Alastair survived repeated wounds; Abaddon was injured but not killed; Cain showed no injury; and Ramiel survived the stabbing. Its ability to kill Lilith and Crowley was threatened or attempted but never conclusively demonstrated. Killing a possessing demon usually sacrifices its vessel.
Appearances & Chronology
- First Mention ID
- SPN-EPS-000045 — S03E01, The Magnificent Seven
- First Use ID
- SPN-EPS-000045 — S03E01, The Magnificent Seven
Archive & Verification
- Canon Status
- Screen confirmed
- Research Status
- Full-series profile pass completed through S15E05 using episode history and transcript-supported canon; individual appearance rows remain eligible for episode-by-episode expansion during the complete series re-research.
- Evidence IDs
- Existing governed evidence retained: SPN-EVD-000083; SPN-EVD-000091; SPN-EVD-000094; SPN-EVD-000098. Later-season evidence requires governed IDs during the episode-by-episode research pass.
- Citation IDs
- Existing governed citations retained: SPN-CIT-000204; SPN-CIT-000205; SPN-CIT-000216; SPN-CIT-000217; SPN-CIT-000218; SPN-CIT-000219; SPN-CIT-000220; SPN-CIT-000221; SPN-CIT-000222; SPN-CIT-000223; SPN-CIT-000224; SPN-CIT-000225; SPN-CIT-000226; SPN-CIT-000227; SPN-CIT-000247; SPN-CIT-000248; SPN-CIT-000262; SPN-CIT-000266; SPN-CIT-000269; SPN-CIT-000232; SPN-CIT-000233; SPN-CIT-000240; SPN-CIT-000242; SPN-CIT-000246; SPN-CIT-000249; SPN-CIT-000250; SPN-CIT-000251; SPN-CIT-000238; SPN-CIT-000239; SPN-CIT-000245; SPN-CIT-000258; SPN-CIT-000259; SPN-CIT-000260; SPN-CIT-000265; SPN-CIT-000270; SPN-CIT-000271; SPN-CIT-000272; SPN-CIT-000273. New full-series citations remain pending governed citation-ID assignment.
- Notes
- Also called Ruby's knife, Ruby's demon-killing knife, the demon blade and the demon knife. Consolidated from episode-level source records; never create a second weapon entity for another appearance. Bulk refresh 2026-08-05: existing governed episode evidence retained; no appearance-level duplicate authorized.
- Last Verified
- 2026-08-05
- Record Status
- Verified profile; full episode-by-episode appearance expansion pending
- Primary Glyph
- GLY-043
- Overlay Glyph(s) / Assignment Status
- Not Applicable — no additional supported locked weapon overlay
- Icon Governance Status
- Primary weapon glyph assigned; character seal or hero art remains a separate future asset and must not replace the icon row.