Castiel believes he is the new God and becomes obsessed with power. Sam, Dean, and Bobby try to find a way to stop him before he explodes with power, even if that means talking to Death himself.

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The leviathans destroy Castiel's body and break loose. Now Sam, Dean, and Bobby have to track them all down. Meanwhile, Sam is beginning to struggle with what is real and what is a hallucination.

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Sam reunites with a childhood girlfriend who is supposedly preying on human brains.

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Sam and Dean investigate murders of people who have their guilty pasts come back and kill them. Could Dean be next?

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Sam and Dean get caught in the middle of a feud between a married witch couple.

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Two Leviathans are impersonating Sam and Dean and going on a killing spree. Now, Sam and Dean are the most wanted criminals in the country.

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An estranged Sam and Dean reunite to solve a curious case in the most psychic town in America, but it's far from happy families for the Winchester brothers.

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Sam runs into Becky and they end up getting married. Dean finds it suspicious that Sam is falling for her and decides to investigate.

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Something is turning all of the people of a small town in New Jersey into cannibals.

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Bobby is close to dying. He must confront his worst memory to escape, before his reaper catches up to him.

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While Dean and Frank try to figure out the numbers from Bobby's clue, Sam tries to help a young girl search for her missing father.

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After attacking Chronos, the time god, Dean is sent back to 1944.

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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.

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Sam and Dean are stumped. Somehow, a group of children's personal fears are becoming a reality and killing off a parent that each child has a certain hatred for.

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Four years ago, Sam and Dean exorcised a demon serial killer. Now he's back for revenge.

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Sam and Dean stumble onto one part of the Leviathan's ultimate plot while tracking down some cursed objects in a small town.

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Lucifer is driving Sam into madness. Desperate to save him, Dean tries to find someone who can help. He finds Castiel with amnesia, instead.

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Garth calls Sam and Dean for assistance in battling a ghost that you can only see when drunk.

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Bobby's spirit tries to help Sam and Dean as they try to find a missing friend inside a haunted house.

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Sam and Dean discover that Frank's hard drive, containing everything on the leviathans, is now in Dick's company building. To retrieve it, they ask for help from one of the employees, a young computer hacker.

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Sam and Dean have possession of a Word of God, but are unable to read it. They find a young prophet that can help, but unfortunately, the angels and leviathans are after him, too.

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To officially kill the leviathans, Sam and Dean need the blood of an Alpha. But Dick knows what the Winchesters are up to and sends his men after them.

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Sam and Dean make a plan to storm Dick's company building and kill him once and for all, with help from Castiel and Meg. Providing Bobby doesn't get to Dick first.

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