Big Bad

Big Bad is a term originally used for the television series Buffy the Vampire Slayer to describe its major antagonists but has since been used by some critics and fans for multiple other shows, including Supernatural.

The title is divided into the main villains and the secondary villains. The Big Bad is the main villain of the season, orchestrating events behind the scenes, while the secondary villain(s) often (but not always) serve the Big Bad, appearing more regularly and antagonizing the heroes. In some cases, there are several antagonists that also work against each other, other than just antagonizing the Winchesters. Some Big Bads are introduced early on into the season and act as the Bid Bad throughout the major arc, while some are later revealed to simply be secondary villains, and are then replaced by the season's true Big Bad or some other character also playing an antagonist role.

Season 1

 * Main Villain: Azazel
 * Secondary Villain: Meg

Season 2

 * Main Villain: Azazel
 * Secondary Villains: Jake Talley and Dean's Crossroads Demon.

Season 3

 * Main Villain: Lilith
 * Secondary Villain: Bela Talbot

Season 4

 * Main Villain: Lilith
 * Secondary Villains: Alastair and Ruby

Season 5

 * Main Villains: Lucifer and Michael
 * Secondary Villains:  Zachariah and The Four Horsemen

Season 6

 * Main Villains: Raphael and Castiel
 * Secondary Villain: Crowley and Eve

Season 7

 * Main Villain: Dick Roman
 * Secondary Villains:  Lucifer (hallucination)

Season 8

 * Main Villain: Crowley
 * Secondary Villains: Naomi and Metatron

Season 9

 * Main Villains: Metatron and Gadreel
 * Secondary Villains: Abaddon and Bartholomew