[WARNING: This article contains SPOILERS for The Flash season 2 finale.]

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How many pieces of fan service and surprises can you pack into a single season finale? Whatever the record, the season 2 closer of The Flash took a good shot with the reveal of yet another fan-favorite speedster, a powerful allusion to Barry Allen's greatest comic book sacrifice, and a closing sequence that is guaranteed to have DC Comics fans talking until the next season debuts.

But to grasp just how much has really changed in The Flash's closing moments, a little knowledge of "The Flash" in comic books is needed - not to 'appreciate' the imagery or references being made, but to know just how much the show could change in its third season. Time travel, alternate futures, a de-powered hero (for real this time) and some imaginative cameos from The CW's superpowered colleagues may all be in the cards - provided you read the clues.

It's not like fans weren't warned that the season finale would by making a bold leap into new territory, but once you realize how much the status quo has changed, even picturing next season is a comic fan's dream come true. Read on for our full breakdown of The Flash: Season 2 Finale Cliffhanger Scene Explained.

Barry's First Trip Home

The Flash Season 1 Finale Barry Nora Allen

The season 2 finale wasn't the first time that fans followed Barry back through time, to the just his mother was murdered. The first time around, he had a choice to make: save his mother's life like he always wished he could - but risk losing every part of his life that formed out of that trauma. Or, leave the past as it was, which meant accepting that his mother's death made him who he was, and gave him happiness, friends and family who loved him.

In the end, Barry made the right choice and let time remain as it should be. Or, more accurately, he stopped himself from changing it. For those in need of a reminder, Barry was prepared to leap in to save his mother as his other self zipped out of the house to usher young Barry to safety, but when he began to make his move, he was urged to stop by his older self. It didn't take much effort - merely a raised hand, and Barry accepted fate, and got to say his tearful goodbyes, assuring his dying mother that he wound up happy after all.

How Things Have Changed

Flash Season 2 Finale Barry

Barry might have found happiness in what he had, not what he had lost, but things had gotten much, much worse for him since then. Not just the death of Eddie Thawne, Ronnie Raymond, Earth 2 Joe West, or having found love and lost it, but basically seeing every bright moment of his life snuffed out soon after. And when his communion with the Speed Force left him recharged and hopeful, watching as Zoom still succeeded in murdering his father was the final straw. Either that or having to travel back in time and ask his other self to sacrifice himself to prevent Zoom from destroying the Multiverse... only to have his wounds reopened when the real Jay Garrick was revealed to be his own father's doppelganger.

All in all, a pretty bad year. So as the rest of the team quietly enjoyed the end of another villain, collectively licking their wounds in the safety of the West household - and Barry realized that, yet again, he was too wounded and scarred to pursue the love of his life - he made a choice. Since the bad now seemed to outweigh the good, the one thing keeping him from using his power to change his entire life was gone.

And he set out to make things right - as he saw it in the moment, at least.

Changing The Past - And The Future

Flash Season 2 Finale Time Travel Changed

Once heading into the timestream, Barry only needed to sense the night of his mother's murder (helped by his younger self's screams) and do what he had failed to before. In short: wait for his opening, and stop the Reverse-Flash from killing Nora Allen. Succeeding in doing just that (although who knows what he's going to do with Eobard Thawne), he guarantees that Nora will live, and all the eventualities that come with it. No father in prison, no living in Joe West's home, and all the possible changes he had previously decided weren't worth the risk.

It doesn't take long to see the cost of his actions either. One look to his other self - the one that had made the first trip back - and the relieved smile on his face (having expected to watch as his mother was killed, and instead finding her to NOT have been killed at all) lasts for just a moment before he begins to dissolve out of existence. Why? Because if Nora never died, then Barry never became The Flash, never travelled back to see the future changed - only the current version of Barry continues as a time remnant of the future that used to be.

The question then becomes: what happens when he returns to the future? Luckily, comic book readers may already have the answer.

Flashpoint Begins

Flash TV Season 3 Flashpoint

The answer lies in "Flashpoint" - the event series penned by Geoff Johns that saw - stop us when this sounds familiar - Barry finally decide to travel back to the night his mother died, and prevent it from happening. Of course, Barry doesn't realize that's what happened; he simply wakes up into a life where his mother is still kicking, yet he is without his superpowers (or the love of his life).

Considering how much The Flash has relied on Geoff Johns' work on the speedster (the premise of the show is based on "The Flash: Rebirth" in which Johns returned Barry to the living, but with the added twist of his mother having died by his enemy's hand), it seems the connection here is meant to be caught.

Kevin Smith had gotten a breakdown of the season's ending while directing his own episode in the season, and claimed that the finale's final moments was a leap that, if taken, needs to be stuck to. Now that fans have seen it for themselves, it seems Smith spotted the similarities too - and if the writers intend to follow the story with Barry losing his powers, the surrounding drama that comes as a result is more than most comic book shows tackle in an entire run, let alone one season.

Flash Flashpoint Season 3

Should fans expect to see Barry's re-writing of history result in not just the loss of his powers, but a war between Atlantis and Themyscira? Bruce Wayne dead while his father became Batman? We wouldn't count on it. But with a shared universe of TV shows - now including ArrowLegends of Tomorrow and Supergirl - there is an opportunity for some horrifying alternate future stories. Not to mention Barry's quest to get his powers back, a showdown with a former speedster nemesis pulled loose from the timestream by his meddling (*cough*ZOOM*cough*), and one last heartbreaking trip to the scene of his mother's murder.

That's what we expect from season 3 of The Flash, anyway, since it's the exact story that the showrunners are alluding to. How far they go with it... well, that remains to be seen.

What did you think of the closing moments of the finale? Were you still reeling from the arrival of Jay Garrick to truly grasp what the final scene meant for the next season? Or have you been expecting "Flashpoint" to be adapted sooner or later? Let us know your thoughts in the comments, and how the other CW shows should be put to use in a possible "Flashpoint" future.

NEXT: The Flash: Man in The Mask Identity & Backstory Explained

The Flash will return to Tuesdays on The CW in Fall 2016.