Plot hole: In episodes where Sam and Dean are required to perform spells/rituals at certain times, the issue not quite seen is that not all clocks are exactly in sync with each other, meaning that the clock they are using could be off by a few minutes especially if dealing with different time zones or time periods. (S07E12, Time After Time).
Supernatural (2005)
1 plot hole in season 7
Hell House - S1-E17
Visible crew/equipment: When Dean, Sam, Ed and Harry have just shot Mordechai, the cameraman's arm is visible on the right-hand side of the screen. (00:33:30)
Sam Winchester: Why'd you let me fall asleep?
Dean Winchester: Because I am an awesome brother. What did you dream about?
Sam Winchester: Lollipops and candycanes.
Trivia: The inscription on John Winchester's gun is Latin, translating to "I will not fear evil."
Question: In the one episode Gabriel attempted to kill Lucifer with his archangel blade. Even though he didn't succeed, why didn't they attempt to do use one before? Couldn't Cas have given them one, or gotten one if an archangel's blade is different then an angel blade (I'm not sure), or would it have even killed Lucifer, because he is an angel after all?
Answer: Angel blades come from angels. It's their angelic magic that makes it special. Therefore, an archangel blade is made magical with the powers of an archangel. They couldn't have just created one or used one, as none of them are archangels.