| “ | Jack, I've killed people who didn't deserve it... my friends– I've killed people I loved. | ” |
Beings killed by Castiel.
Angels
Archangels
- Raphael - Exploded at the molecular level while empowered by the souls of Purgatory.
Intelligence Angels
- Ion - Pushed an angel-killing bullet through his right eye to escape Ion and Crowley.
Grigori
- Jack's Captor - Stabbed in the chest with an angel blade.
Regular Angels
- Adam's Angel Escorts - Stabbed with an angel blade at Adam Milligan's resurrection site.
- Alternate Castiel - Stabbed in the abdomen with an angel blade.
- Balthazar - Stabbed through the back with an angel blade after discovering Balthazar had betrayed him to the Winchesters.
- Bartholomew - Stabbed in the abdomen with an angel blade in self-defense.
- Daniel - Stabbed through the back with an angel blade to save Hannah.
- Duma - Stabbed with an angel blade after she threatened John and Mary Winchester's souls in Heaven.
- Efram - Stabbed in the chest with an angel blade.
- Hael - Stabbed in the chest with an angel blade after being pressured to become her vessel.
- Ishim - Stabbed through the back with an angel blade to save Lily Sunder.
- Jonah - Stabbed in the abdomen with an angel blade.
- Mansion Attackers - Threw an angel blade into the chest of one during the Skirmish at Balthazar's Mansion. Smote the second along with the rest of the Raphael Loyalists after declaring himself the new God.
- Pharmacist Angel - Stabbed in the abdomen with an angel blade.
- Metatron's Assassins - Killed with an angel blade in self-defense during Operation: Lee Harvey.
- One of Zachariah's Guards - Stabbed with an angel blade outside the Green Room.
- Raphael Loyalists - Smote in Heaven after declaring himself "the new God."
- Raphael's Spy - Smote in Heaven after declaring himself "the new God."
- Rachel - Stabbed with an angel blade in self-defense.
- Samandriel - Stabbed in the stomach with an angel blade while under the control of Naomi.
- Theo - Throat slit and grace absorbed then smote.
- Three of Malachi's Faction - Stabbed with an angel blade after stealing Theo's grace.
- Zachariah's Foot-Soldiers - Stabbed through the neck and in the back respectively with an angel blade in order to save Sam and Dean Winchester.
Rit Zien
- Ephraim - Stabbed in the chest with an angel blade.
Nephilim
- Jane - Stabbed through the neck with an angel blade and cut out her heart for Metatron's spell.
Demons
Princes of Hell
- Dagon - Incinerated while empowered by Jack.
Regular Demons
- Belphegor - Smote by Castiel after he betrayed the Winchesters to become the new Ruler of Hell.
- Bunker Incursion Demons - Smote one to save Sam's life. Killed three others alongside Sam and Gabriel.
- Crowley's Assassins - Smote to protect the Winchesters and Bobby Singer from an attack.
- Castiel and Lucifer's Attackers - Killed alongside Lucifer in Crowley's old lair.
- Castiel's Captive - Tortured for information on the location of Cain then stabbed through the chest with an angel blade.
- Demon Medics - Smote by a memory-less Castiel outside the Northern Indiana State Hospital.
- Dipper - Smote in Crowley's old lair after being released from his cell by Lucifer.
- Ellsworth - Forced back into his vessel and then smote so that he could not tell the Winchesters that Crowley is alive.
- Ellsworth's Hunters - Two demons capturing monsters for Elsworth who were smote by Castiel to keep the Winchesters from finding out the truth about Crowley's survival.
- Malfayan - Stabbed with an angel blade.
- Marcus - Smote by Castiel at the Northern Indiana State Hospital to save Sam Winchester.
- Meg's Captors - Smote at the Murray Hotel while rescuing Meg.
- Monster Prison Guards - Killed when Castiel destroyed Crowley's Monster Prison and all inside it.
- One of Dean's Captives - Smote to save Dean's life.
- One Iowa Factory Guard - Smote while rescuing Kevin Tran and the future Prophets.
- Pestilence's assistant - Stabbed in the abdomen with the demon-killing knife after defeating Pestilence.
- Three Tablet Hunters - Smote two, stabbed a third with an angel blade.
- Two of Claire's captors - After taking Claire Novak as his vessel briefly, Castiel smote two of her captors.
- Hundreds of demons - As an angel, Castiel has killed hundreds of demons over the millennia.
Monsters
Djinn
- Alden Roy - Stabbed several times in the chest with an angel blade.
- Brigitta - A Djinn held prisoner by Crowley in his prison when Castiel slaughtered the prison's inhabitants.
- Several members of a Syrian Djinn pack - Killed by Castiel during his quest for Fruit of the Tree of Life.
Leviathans
- Dick Roman - Briefly restrained so Dean could stab Dick through the neck with the Bone of Righteous Mortal Washed in the Three Bloods of Fallen.
Rugaru
- Captured Rugaru - One of the prisoners in Crowley's Monster Prison killed by Castiel when he killed all of the monsters within the prison.
Jefferson Starships
- Around a dozen Jefferson Starships - Blasted with holy white light.
- Cop Jefferson Starship - Decapitated by Castiel with a machete before it could attack Bobby Singer.
- Prisoner Jefferson Starship - Brutally tortured by Castiel for Eve's location and then decapitated.
Vampires
- Lenore - Smote at her request.
- Unnamed Purgatory Vampire - Smote while fighting alongside Dean and Benny Lafitte.
Werewolves
- One of the Marina Werewolves - Stabbed in the heart with an angel blade.
Zombies
- An unnamed Croatoan zombie - Decapitated with a shotgun blast to save Sam's life during the Raid on Niveus Pharmaceuticals.
Other Monsters
- Crowley's Monster Prison - Killed all of the monsters within the prison at the Winchesters' request.
Humans
Hunters
- Hundreds of Dean Winchester clones - Killed in various ways by Castiel as part of his training under Naomi.
Vessels
- Alfie - Killed along with Samandriel by Castiel.
- Alternate Jimmy Novak - Killed along with the alternate Castiel by Castiel.
- Ann Morton - Killed along with the demon possessing her by Castiel.
- Balthazar's vessel - Killed along with Balthazar by Castiel.
- Bartholomew's vessel - Killed along with Bartholomew by Castiel.
- Efram's vessel - Killed along with Efram by Castiel.
- Ellsworth's vessel - Killed along with Ellsworth by Castiel.
- Ephraim's vessel - Killed along with Ephraim by Castiel.
- Duma's vessel - Killed along with Duma by Castiel.
- Gloria Lewellen Jacobson - Killed along with Hael by Castiel.
- Ion's vessel - Killed along with Ion by Castiel.
- Ishim's vessel - Killed along with Ishim by Castiel.
- Jonah's vessel - Killed along with Jonah by Castiel.
- Raphael's second vessel - Killed along with Raphael by Castiel.
- Theo's vessel - Killed along with Theo by Castiel.
- Wendy Rice - Killed along with the demon possessing her by Castiel.
- Numerous other vessels - Killed along with the angels and demons possessing them by Castiel.
Other
Four Horsemen of the Apocalypse
- Pestilence - Cut off his ring with the demon-killing knife, leaving him permanently incapacitated.
Reapers
- Billie - Stabbed through the back with an angel blade to break her deal with the Winchesters. Reincarnated as the new Death.