10 Dumbest Decisions Made By Supernatural Characters

10. Sam Trusting Ruby

Introduced in Season 3, Ruby was always a mysterious character that many fans and the Winchesters were hesitant to trust at first. As obvious as it is now, Ruby had been playing Sam from the very beginning, manipulating and gaining his trust, eventually starting an awkward sexual relationship with him.

Ruby never had Dean’s stamp of approval as, after all, she was a demon. Even when Sam promised Dean he would never drink Demon blood again, it was Ruby who egged him on trying to turn Sam against Dean in making him believe that Dean was just jealous that he doesn’t have powers of his own.

In the decisive moments of Season 4’s final episode, it is revealed that Ruby was playing Sam all along (surprise, surprise), working under Lilith's orders to release Lucifer from his cage and jumpstart the apocalypse. All throughout Season 4 she was manipulating Sam, pretending to be on his side and “helping” him gain strength and control of his powers so he could ultimately be the one who set Lucifer free.

However, it’s ironic that Ruby was killed by the two brothers with her own demon-killing knife she introduced to the brothers to gain their trust.