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Poll Supernatural Showdown: Best 13th episode in 10 seasons Route 666
Dean gets contacted by his first love, an African American woman, about racist murders that occur on a desert route, caused by a truck that seems driver-less.
Houses of the Holy
The Winchesters investigate a spate of murders committed by people who were apparently visited by an angel and told to carry out "God's will" and kill those who have sinned. For Sam it's easy to believe it to be the case. Not so for easy Dean, who believes they're dealing the confused and angry spirit of Father Gregory, a man murdered on the steps of his church in an attempted robbery. While checking up on a lead Sam is visited by the angel and told to kill someone.
Ghostfacers
Sam and Dean inexplicably encounter the Hell Hounds while investigating a case that John failed to crack years earlier and become fixtures in their pilot for a reality show called Ghostfacers.
After School Special
Sam and Dean investigate a haunting at one of their old high schools where we will see what school was like for the brothers.
The Song Remains the Same
The renegade angel Anna escapes from her prison in heaven. She travels back in time to kill Sam and Dean's parents so that Sam is never born, and cannot be the vessel for Lucifer. Castiel sends Sam and Dean back to stop Anna.
Unforgiven
Sam starts to have flashbacks to a case he worked on with Samuel before he reconnected with Dean. Sam receives a mysterious text with coordinates to a small town, so the brothers decide to investigate. Dean is surprised when the townspeople start telling him some of the things Sam did while he lived there.
The Slice Girls
Sam and Dean go up against the Amazons as they go on a killing spree. But it's twice as difficult for Dean because one of them is his daughter.
Everybody Hates Hitler
Sam and Dean go up against a group of Nazi necromancers.
The Purge
Sam and Dean apply for jobs at a wellness spa so they can investigate the murders of guests who have had the fat sucked out of them.
Halt & Catch Fire
To take his mind off of the Mark of Cain, Dean goes hunting. They track down a ghost that is killing college students through electronics and the internet.