When a show has run for over a decade and included hundreds of characters, it is easy to see how it could lose focus on a number of plot threads. It isn’t possible to keep track of all the storylines that have been in place. Once one arc is completed, or swerved into another, it can be left ignored for years to come or never resolved at all. Stories that were relevant in say Season 5 or Season 6 would most likely not be a talking point in Season 12 or 13. The only way to remember all the stories that were going on is to keep track of them regularly by either binge-watching the show or by being an ardent fan right from the start.
Supernatural has fans that fit both these criteria. Someone who had been born when the show started in 2005 will be a teenager now, while those who had been teenagers at the time are now in their late twenties or early thirties. These demographics follow the show religiously and keep in mind the storylines that have been seen since the first season.
The show’s storytelling has always been such that one plot begins where the previous one ends. There has never been an arc that has begun without the seeds planted beforehand. While this is a neat way of fashioning the plot, it does have the effect of abandoning the leftovers of the story that had been in effect beforehand. Many have been resolved after a number of years, but a whole lot still remain up in the air as of writing.
30 Adam's Fate
No list would be complete without mentioning Adam, for Supernatural has done him wrong for 8 years by this point. Sam and Dean may have grown up, but Adam Winchester would still be only 28-years-old as of 2018. That is if we’re counting Earth years because Adam is existentially over thousands of years old now.
The elder Winchesters have made no attempt to rescue him.
The only mention the poor kid got was in Season 10 where a play based on Supernatural featured Adam. Even then the two brothers could only share an uneasy pause before forgetting about their youngest sibling once more.
29 Sam's Reluctance To Gank Innocents
In Season 11, Sam felt immense guilt over his part in releasing the Darkness into the world, thereby causing the passing of hundreds of people in the first episode alone. Sam carried his guilt over to his usual practice of ending Demons by refusing to go through with it. Dean was perplexed at Sam’s hesitancy toward it, but Sam would explain that exorcising the demon allowed the original vessel to survive.
It was a good shift toward reclaiming the lost humanity of Sam, however, this only lasted a couple episodes, after which he resumed stabbing innocent vessels without pondering over the act.
28 Sam's Demon Powers
Seasons 1 through 5 focused mainly on Sam’s connection to demonkind, and his growing powers that were strengthened after ingesting lots of demon blood. Season 5 brought these powers to their peak by demonstrating Sam’s ability to end Demons by a simple thought.
We never saw these powers again.
As soon as Season 6 began, Sam had lost these abilities and there have been no mentions toward it since either. Now, 8 years later, it doesn’t seem likely we’ll ever see Sam in demon mode again.
27 Castiel's Non-Existent Mojo
The blame for this one needs to be placed on pre-season statements from Misha Collins rather on the show. In the series, Castiel had been painfully underpowered for a number of seasons before the Season 12 premiere, but Misha Collins had claimed Castiel would have his “Mojo” back starting from Season 12, akin to his supremely powered self in Seasons 4 and 6.
There was no semblance of this power in the slightest. In fact, in Season 12’s premiere, Castiel got manhandled by a simple human being wearing Enochian Sigils on handcuffs. What’s more is that he had a 2-on-1 advantage on her with Dean in his corner and yet they were still clobbered.
26 All Of Lucifer's Motives (Seasons 11-13)
Lucifer’s story shifted starting from Season 11. He stated his intention to wreak havoc, but found focus once Jack’s impending birth was on its way. Thereafter, the devil was laser-focused on raising his son. His entire story in Season 13 comprised of attempting to locate Jack in order to prove his mettle as a father.
The story took a mighty swerve in the finale.
Once Jack refused to leave Sam and Dean behind, Lucifer quickly stole his son’s grace and professed his intention to rule the galaxy. This contrasted completely with his earlier sole focus on the love for his son.
25 We Never Got Villainous Sam
After Dean made the deal to bring Sam back to life in the Season 2 finale, Azazel boasted to him that the Sam Dean had brought back wasn’t the same boy that had left the world. Instead, the resurrected Sam was a sinister counterpart to the benevolent one Dean had loved. Season 3’s story looked to focus on Sam’s turn for the worst.
Yet, Season 3 Sam was a loving brother who would relentlessly search to save Dean’s soul. Along with that, Sam was never more kind-hearted to other people than he was in Season 3. So was it all a bluff by Azazel?
24 The Scorching Fight
You will remember when your lungs couldn’t contain the laughter that reverberated through your chest when witnessing the battle between Dean and Lucifer in the Season 13 finale. It was special effects at its worst with both men clearly dangling by cables.
This fight had been preceded by years’ worth of dread.
A fight between Michael and Lucifer was certain to scorch half the planet. The world was supposed to be torn in half, but the fight we saw didn’t even shatter the church’s windows! There’s no excuse either as both Michael and Lucifer were vastly more powerful this time.
23 The Katako Kid
Jesse Turner was unlike anything we had ever seen on the show. The boy could turn an angel as powerful as Castiel into a minor toy and still go about as if it wasn’t a big deal. Jesse fled his home due to his true species being the son of Lucifer.
Those events were almost ten years ago, meaning Jesse has been MIA for eight years since the apocalypse has been averted. What’s been keeping this kid in hiding? He must be almost twenty by this point and it’s a wonder there has been no murmur of his whereabouts.
22 All Of Supernatural: Bloodlines
Supernatural: Bloodlines’ story was horse manure. While Wayward Sisters’ premise held great promise, it was ultimately bad in execution. Both backdoor pilots failed, but Wayward Sisters still has a shot at telling its stories due to the characters’ presence in the main series.
Bloodlines’ story will never be resolved.
At the end of the episode, the lead character received a phone call from his long presumed deceased father, and the circumstances behind it were a mystery. Too bad no one cared for the show in the slightest as that phone call has been hanging for five years by this point.
21 Still Partying, Garth?
Garth Fitzgerald IV was one of the breakout recurring characters on Supernatural. Like Felicia Day’s Charlie, Garth had the lovable charm one would find in a younger sibling they never wanted; which is why his absence has been so conspicuous since Season 10.
Season 12’s storyline had showcased the Men of Letters from England seemingly eradicating all of the monsters in the US. Garth was never mentioned, nor did the Winchesters even once display concern that their friend might have been part of the monster purge. Is he in purgatory or still munching on raw meat?
20 Forgetting About Kevin
Season 11 did resolve Kevin’s soul being stuck in the veil, but it didn’t answer why Sam and Dean had abandoned his ghost for all of two years. In Season 9, Dean had movingly professed his brotherly love for Kevin by calling him his family.
These may have been just words after all.
Despite knowing that Kevin was leaving with his mother as a ghost in Season 9, the brothers never kept in check with him since. We should also mention Kevin’s mom, who must now be without the ghost of her only boy without explanation.
19 Is Benny Still Alive?
Benny Lafitte did the impossible by becoming the first monster Dean Winchester cared deeply for. Before meeting him, Dean would consider all monsters to be lacking a soul and wouldn’t hesitate to end their lives. This affection was returned by Benny who agreed to go back to purgatory to rescue Sam.
Once he got there, the last we saw of Benny was him getting overpowered by other monsters. We never found out if he survived this encounter or not as Benny was clearly still alive before Sam left. His only appearance since then has been as a hallucination in Season 10.
18 The Hands Of God
A storyline that was developing in Season 11 was the discovery of the Hands of God. These weapons were relics that contained powers from Chuck himself. A good part of Season 11 focused on the heroes’ attempts at acquiring these weapons in order to combat the Darkness.
The story seemed to be heading toward these artifacts the same way it had with the Angel/Demon/Leviathan tablets. Crowley and Sam mentioned their interest in further locating other Hands of God relics but after the second part of Season 11, there has been no mention of them yet.
17 The First Son Conundrum
It was firmly established that Lucifer was the second son, like Sam. Lucifer even mentioned this to Sam in a discussion in Season 5, openly calling Michael his older brother. However, in Season 11, Amara would address Lucifer as Chuck’s first son.
This seemed to have been a retcon, but there were too many clashes with the storyline for it to be canon.
The prophecy of Michael and Lucifer’s battle was for Sam and Dean to act as their vessels and thereby causing the older brother to combat the younger one. What Amara meant is still uncertain.
16 Jacob Pond's Revenge
Dean was once quick to finish off monsters as he deemed them all to be too bloodthirsty to remain harmless. Acting on this belief, Dean ended the life of Sam’s friend Amy Pond. He didn't know Amy’s son witnessed this event. Dean chose not to do the same to the boy.
The boy, though, was defiant in his vengeance toward Dean, stating he would one day track Dean down and finish his life. Now 7 years later, the boy should be old enough to follow through with this threat, but looks like he’s forgotten all about it.
15 The Fate Of John Winchester
We haven’t seen a chronological appearance from John Winchester since the second season finale. John had escaped the underworld to hold back Azazel, allowing Dean to destroy the demon. Since then, we’ve had no answer from anyone as to what happened to the Winchester patriarch.
Despite Mary’s resurrection, John’s whereabouts are shrouded in mystery.
He was said to not be in heaven by Ash in Season 5 and Castiel would have known John would have been there during the angel’s time in running heaven. Most likely, John will only be seen when the series finale is due to be out.
14 Status Of The Leviathans
The leviathans were the main antagonists of Season 7. Unfortunately, their stay on the show was marred by inconsistent writing toward their powers. On one hand, they had the ability to instantly dispose of angels, but on the other hand, they were so easily beaten through the splashing of Borax on their faces that any normal human could defeat them with little trouble.
Since Dick Roman was sent back to Purgatory, all the leviathans have been missing. There has not been a single mention of them since Season 8. On Earth, the leviathans seem to have completely disappeared.
13 Azazel's Original Plan
The writers had clearly not foreseen the show lasting so many seasons and the story was navigated toward where we saw the Season 5 finale end. In it, it was stated that Sam was always meant to be Lucifer’s vessel.
Except, Azazel had other plans in Season 2.
In this season, Yellow Eyes didn’t care much that Jake had ended Sam’s life and was more occupied with opening the Devil’s gate and forming a demon army with Jake in charge. This original plan was modified later on to show Azazel as a Lucifer fanatic, but Lucifer never needed a demon army, did he?
12 Original Michael's Status
Season 13’s storyline focused on Alternate Michael’s attempts at opening a gateway to the real world in order to take over. Lucifer and Gabriel both interacted with this Michael, with the two referring to the Alternate Archangel as their brother despite this Michael not being part of their universe.
In the end, Alternate Michael prevailed and now runs free. But the question is what happened to the original Michael? The last we heard he was still in Lucifer’s Cage, but the way things are heading it would appear the writers have abandoned him down there.
11 Sam's Relationship With Amelia
Nobody likes it when any of the main characters get love interests. These women are seen as hindrances to the plot, and fans would rather witness friendship-filled moments between the leads.
An ill-received relationship was the one between Sam and Amelia.
During Dean’s year in purgatory, Sam settled down with this woman. This bliss was interrupted when Dean returned and we got some daytime soap-like drama with Sam, Amelia, and her previously believed deceased husband. Last we saw Amelia, she had left her spouse to be with Sam, who instead abandoned her in favor of Dean.