Mid Season Twist / Supernatural

• Season 1: The boys' dad calls them.
• Season 2: The brothers meet Ava and she disappears.
• Season 3: It's revealed that demons were once human.
• Season 4: Sam is addicted to demon blood.
• Season 5: The boys face off against Lucifer. It ends badly.
• Season 6: Castiel reveals that Sam came back without his soul. Eve is released from Purgatory.
• Season 7: Dick Roman becomes the Big Bad. Sam's hallucinations get worse.
• Season 8: Castiel returns (outside of flashbacks). Introduction of Naomi.
• Season 9: Gadreel takes over Sam's body and kills Kevin.
• Season 10: Rowena is revealed to be Crowley's mother, and starts manipulating Crowley in order to reach her own goals.
• Season 11: The Darkness is revealed to be God's sister. Shortly after that, Lucifer returns, setting up a Big Bad Ensemble.

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