screenrant.com - por RHYS MCGINLEY - Supernatural's Sam was thrust into doing evil things por way of possession multiple times but also acted as a villain through his own choices.
screenrant.com -BY RHYS MCGINLEY - Supernatural's Dean makes many mistakes that end up causing serious harm, but he also acts as a villain thanks to possession and the Mark of Cain.
screenrant.com -BY SAIM CHEEDA - Dean's pairing with Castiel led the way for their character development and cemented them as relationship goals in the eyes of many supernatural fans.