Supernatural is not one of the shows I watch and therefore I do not cover it. However, since I compiled some finale spoilers for a friend I thought I would share them with you all. Enjoy!
Dean is at Bobby's house and offers him some whiskey. Bobby has helped Dean out with something. Sam looks at a large dusty book, it is the Key of Solomon. Sam and Dean look at a drawing that is a circle with interlocking squares inside of it. Bobby says that they are protective circles. Bobby is worried that Dean and Sam are into things too serious, many more demons than usual. Bobby thinks some sort of storm is coming. Later on Dean punches Meg in the face. Dean is really upset and thinks Meg is lying about someone (a "he") being dead. Bobby tells Dean to be careful with Meg because she is possessed.