A haunting detail that I just noticed about S1's Nightmares In season one's "Nightmares", one of Buffy's biggest fears is that she is buried alive. She has to fight her way out of her fresh grave.

On rewatch, this scene is so haunting as it raises the stakes even more in Season 6 when this happens again for real. For me, it just added so much weight and even more sadness to "Bargaining" knowing that Buffy is forced to live out one of her biggest nightmares yet again 5 years later.