Being a dark fantasy series doesn't mean Supernatural can get away with instances where plot holes and inconsistencies open up. This is because the series has defined an established logic of its own universe, meaning these aspects have to be adhered to since the events circle around this canon. Still, there are more than a few times where Supernatural has chosen to outright ignore its own logic for the benefit of furthering the plot. What’s more, these inconsistencies were never addressed in the show, making them illogical points that will continue to bug fans now that the series has ended.
Here are some times where Supernatural didn’t care to follow its own logic.
Lucifer And Michael's Battle Was Supposed To Destroy The Planet But Nothing Actually Happened
The purpose of averting the apocalypse in Season 5 is to avoid a world-ending scenario. It's mentioned by several characters that Michael and Lucifer's battle would destroy half the planet, which motivates Dean not to give Michael consent to possess him.
However, this battle is actually seen twice, with the first instance being the Season 12 finale, where Alternate Michael empowers Dean and fights Lucifer, who is even more powerful than normal due to stealing Jack's powers. It takes place again in Season 15's "Inherit the Earth," where the main-universe Michael fights Lucifer. There is no collateral destruction on either occasion, despite Lucifer meeting his end both times.17874Pretty big plot hole?
'Christo' Being The Word That Exposes Demon Identities, Only To Never Be Used Again
The Season 1 episode "Phantom Traveler" introduces the word "Christo" as a way to expose demons, as hearing the name causes them to show their black eyes. This sounds like a very convenient way to find demons, especially considering how frequently the Winchesters come across them in the future. However, the word is never used again, with the only other reference appearing in the Season 14 episode "Optimism," where Jack uses it on someone who isn't a demon.
It wasn't explained why "Christo" was phased out, although it's clear it was ignored by the show because it would've made fighting demons too easy.14451Pretty big plot hole?
Lucifer Slaying Death Despite Death Being More Powerful
The original Death claimed he was strong enough to destroy God, and Lucifer was shown to fear him, as archangels aren't as powerful. In Season 15, episode 19, "Inherit the Earth," Lucifer is resurrected by God in order to snag his death book from the Winchesters. Lucifer takes the life of a Reaper named Betty to turn her into the next Death, as this is the only way for a new Death to be made.
While Betty is confirmed to have Death's powers, she is somehow slain by a simple snap from Lucifer after she reads the death book. Betty should have been more powerful by that point as the new Death, meaning this should have been impossible since Lucifer is an archangel.15062Pretty big plot hole?
John Winchester Had A Dad In The '70s Even Though Henry Winchester Disappeared In The '50s
When Dean is sent to 1973 in Season 4, episode 3, "In the Beginning," he meets a young John Winchester. Here, John's acquaintance specifically asks him to say hello to his father, to which John agrees.
And yet, the Season 8 episode "As Time Goes By" shows John's father Henry time traveling from 1958 to 2013, where he meets his grandsons and perishes in the future. It's also stated that John thought his father abandoned him his whole life, but that shouldn't be possible if he was supposed to have a father in 1973.16172Pretty big plot hole?