The Player Character R-L's NameIs maybe a play on pronunciation on his/her name as Aurel or Aurelia, the names derived from Aureus meaning "golden" in Latin. Maybe R-L has Eagle Vision like Desmond?
One of the fantastic elements introduced in the game will be the mythical Bermuda Triangle
The game will be packed with references to Pirates of the Caribbean.Self-explanatory.
Connor Kenway will reappear as a playable characterBecause seriously, ACIII explicitly said that Connor would have further adventures. The developers might even do the same thing as in Revelations—have the playable ancestor be Connor, but have Connor use Applied Phlebotinum to replay the memories of his ancestor, so that the player can switch between the two storylines. Since this is a new numbered title, the new Assassin would probably be more prominent though.
Assassin's Creed IV will feature Edward teaching Haytham because the present day character was related to Haytham's younger sibling/half-siblingNow that Desmond's saga is over with the new central character is looking to the past and finding Edward and will not be related to Connor directly.
Achilles will appear in Assassin's Creed IV.He will either make a cameo or be a major character as Edward's student.
Edward's home base will be...
Edward's crew will be Locked Out of the Loop.As Blackbeard asserts in the trailer, it is unwise to meddle in his personal affairs. There are probably only a handful of high-ranking confidants that know the truth of the Assassin/Templar conflict, while the remainder of the crew are your average buccaneer who either don't give a rat's arse, decide to not to get involved, or are simply ignorant of the goings-on behind the closed door of the captain's cabin.
Assassin recruits will not be members of your crew.Instead, they will be other captains in your fleet. Rather than having special footsoldiers to summon in combat, you summon whole ships to assist you in naval combat.
Edward's ship will fight the Aquila, leaving it in the state Connor found it in Assassin's Creed III.
Edward is a Villain Protagonist.Consider that, in the launch trailer, Edward seems to be a bit more cold and have looser morals (killing a target then walking out with his lady) than all of the previous Assassins combined. So much that even Blackbeard is scared of him. Not to mention that Haytham took on the directly opposite ideology. It's possible that Edward will hit this trope at some point. Also, it might make a good parallel to Haytham's relation with Connor.
There will be a mission that takes place in the Royal Opera House in London.Haytham Kenway mentions in the opening level in the third game that his father brought him to the Royal Opera House when Haytham was very young, and that he remembers very little of it. There could be a mission in Black Flag that shows this, perhaps even an assassination mission. This would serve as an effective call back to Assassin's Creed III.
Henry Rollins will be in this game somehow.How can you have something named Black Flag without Rollins?
Bartholomew "Black Bart" Roberts will be a Templar pirate.The most successful pirate of his time, Black Bart has plenty of traits that would make him a candidate for the Templar Order during the Golden Age of Piracy. He was much more bloodthirsty than his peers, and was a Faux Affably Evil gentleman who dressed in fine clothes and jewelry. Plus, we know that one of his prized possessions was a bejeweled crucifix, so the iconography is there. And think about the contrast between rakish, unkempt pirate turned Assassin Edward and groomed, fashionable pirate Templar Bartholomew.
Part of the game's story will take place during the War of the Quadruple Alliance.Specifically, the Battle of Nassau, which is one of the major hubs.
The player character will turn on Abstergo.If they are merely hired by Abstergo they will relive both Edward Kenway's memories and some of Desmond's that has been hacked back in by Erudito. Find out that Abstergo are the Templars and turn against them as a result. If they were full members of Abstergo they will use stealthy and risking tactics to help out the remaining Assassin's out in the world. Either way using the animus will bite Abstergo in the ass again.
ACIV will involve a Templar Cabal of Pirate Hunters.Since the protagonist is a pirate, nothing more fitting than Templar conspiracy of Pirate-hunters [and men of the royal navy] who seek to bring forth the End of an Age of the golden age of piracy [and given the period the game is set, at the very end of the golden age, they seem to be succeeding]. Possible members being:
Edward will be reminiscent of Altair.That is, early Altair before he was demoted for his recklessness. Specifically in terms of a libertarian, carefree interpretation of the creed "nothing is true, everything is permitted."
Blackbeard will be The Mentor to Edward Kenway.By showing him the ropes of how being a pirate works, etc. Bonus points if he suffers from Mentor Occupational Hazard and Edward decides to go after his killer.
The 'you' in this game's modern story played AC3's multiplayer.When you reach Level 50, you unlock a development diary video where Alan R. tells you that he wants to run further investigations on you, while the Erudito version has Erudito claiming he wants to contact you. Obviously, nothing actually happens to you, as there are no more videos to unlock, but it could be possible that you were simply beta-testing the game at the time. Maybe, you are promoted at the start of AC4 to a researcher of Edward Kenway, and will be challenged to think for yourself as Erudito tells you to.
Captain Jack Sparrow is an Assassin.It would fit with the bird theme-naming.
The framing story will show the beginnings of a Templar-Assassin alliance.With Juno's escape and the death of Vidic and Desmond, the two ancient societies will temporarily join to fight the new threat. Expect the Templars to take after Haythem more than any other Templar, and the Assassins to be fully prepared for a You Have Outlived Your Usefulness scenario.
New group of ProtagonistsThe foreshadowing in the online parts of previous games will come to fruit in the modern meta-narrative as either a customisable protagonist or a selection of different people (a la Far Cry, another Ubisoft game). The voice of the hacker you hear in the epilogue of III will be secretly guiding you while you work inside Abstergo.
Abstergo is looking for the descendant of EveSubject 16 told Desmond to find Eve's DNA, in the Cinematic trailer Edward is shown to hold what looks like a glass cube with something red sealed in the centre. Perhaps this is some blood or tissue, more specifically Eve's blood or tissue. Abstergo will be looking through Desmond's (or maybe his father's)ancestors' history to try and find this sample so they can recover it and analyse the DNA and find Eve's modern day descendant.
The genetic memories of Edward were harvested from Desmond's corpse.His body was taken by Abstergo. It may be possible that they used it to view his ancestor's memories.
There's an even Bigger Bad than JunoShe'll probably go about ruling the world with an iron fist, but it's all to prepare humans for a bigger threat, whether it's from the past or in the future. Even with their new iron goddess, the Assassins and Templars will still be at each others throats.
AC4 will have minigames like in AC3, except more pirate-themed(crosses fingers) Please have Liar's Dice, please have Liar's Dice...
Edward faked his death, and fathered another childIf there's some way he's still alive after the end of the Revolution, he'd be in his 90s! Though then again, it's likely since assassins like Altair and Ezio lived to a ripe old age in times where the mortality rate was at 30-40.
The player's non-Animus identity is EruditoWhat with the whole "hacking Abstergo from within" and whatnot.
Edward's tattoos work like Jason Brody's tattoosDoing guild challenges like the previous AC games gives Edward tattoos as well as strengthens him.
The modern character is actually ShaunHe did consider wanting to go into the Animus during AC3. Perhaps he finds out that since Edward is his ancestor, he's also a distant relative of Desmond and William as well. His time in the Animus also gives him eagle sense as well as a lifetime experience of parkour.
When Blackbeard dies, he or someone close to him will have a Piece of EdenAnd it will make Blackbeard's decapitated body swim laps around the ship. Or at least make it look like it...
There will be DLC focusing on James Kidd/Mary ReadMakes sense, since Mary had a baby just a few days before she died, making almost her entire life open to play, and Abstergo would likely want to know what she was up to.
Abstergo will get quite a lot of Precursor data from John's/Roberts' bodyWhen Roberts died by Edward's hands, he wanted him to destroy his body. John got himself shot to death while in an Abstergo building. Accessing a security camera archive video in the basement afterwards reveals they have the body in cold storage. Whatever they find from his genetic memory won't be good.
The Abstergo Shareholders meeting and Olivier's disappearance are part of the story in Watch_DogsOne of the files you can obtain shows that Abstergo has had a hand in developing the ctOS, not to mention both the Shareholder Meeting and the game are in Chicago.
In the Freedom Cry DLC Adewale will end up killing Woodes RogersThe DLC takes place in 1730 (and possibly onwards), and Rogers died in 1732. Edward also vowed to track him down, but had settled into a family life at that time, leaving it up to Adewale, who knows of Rogers' Templar activities, to do the job.
John was EruditoErudito had been keeping himself fully hidden until his body was overwritten by Aita. Now that he's dead, the Assassins will probably end up losing quite a bit of ground they gained over the last year.
About " reincarnation" The Sage, actually Aita, came to be because Juno spread Aita's genetic information through all of humanity. A Sage is "reincarnated" not by the soul being reborn in a new body—as it has been confirmed that there are no supernatural elements to Assassin's Creed—but by a significant-enough degree of Aita's genetic code building up in a single individual over many generations, similar to how eagle vision comes from one having a significant-enough degree of First Civilization heritage in general. Considering that Those Who Came Before created the Apples of Eden, which can cause impossible feats to happen if enough people are enthralled by it, it's not too much of a stretch that Juno would be able to pull off what amounts to reincarnation.
R-L is "Eve"Clay somehow found out about Juno/Aita's intention to find a host body that Juno could use to take over the world (and let's face it, if Juno wants to take over the world she'd need a host body that can both use, and be unaffected by, the Pieces of Eden), and pleaded with Desmond to find her before they did, though obviously Desmond's death would complicate things a bit.
Clay not only attempted to hitch a ride in Desmond's head......when Desmond's genes were put into the Animus cloud, both he and Desmond were resurrected as Ghosts in the Machine and will aid the protagonist in the next game from within the Animus, possibly tying into the above WMG.