Piece of mind
Assassin's Creed's history-spanning adventures aren't that difficult to grasp - go back in history, stab people, profit. But there's also a modern-day storyline that holds it all together, giving weight and relevance to the choices of past Assassins - that is a convoluted pile of twisted absurdity. Even poring over every database entry in every single game won't get you the full story, because much of the story's hidden in side-content and a social hub website called Assassin's Creed Initiates which is now defunct, its information scattered to the digital winds.
But the truth is out there. Years of careful study (and the fine work of archivists at Access the Animus) have helped pave the way to a simple, easily digestible telling of everything that's happened in the modern-day Assassin's Creed story since December 2012. That marks the end of AC3, when Desmond Miles dies to save the world, and the goddess Juno (a being from the Precursor race that created humanity) escapes imprisonment and begins a mission to enslave humanity. Maybe keep aspirin nearby for this one.
WARNING: Spoilers throughout, with spoilers for AC Syndicate in the final slide.
May 2013 - William gives up his position as Mentor of the Brotherhood to Gavin Banks and goes into hiding
Despite being the quintessential disapproving father who expresses parental affection exclusively through stone-faced indifference, William Miles (father to Desmond Miles and Mentor of the Assassin Brotherhood) can only keep a stiff upper lip through so much. After his son comes to a violent end protecting Earth from an exceptionally deadly sunburn, William falls into a deep depression and, finally broken by circumstance, is unable to carry on with his duties as Mentor.
He passes that kerosene-soaked torch onto long-time friend Gavin Banks, leader of the Altair II, a ship-bound Assassin base that keeps some of the last vestiges of the Assassin Order mobile and under the Templars' radar. His last "gift" before vanishing into the ether is an encrypted notebook packed with everything he knows about the Order, and hints about where Gavin and company should go next.
May - October 2013 - Shaun and Rebecca infiltrate Abstergo Entertainment
In order to establish "eyes and ears" in America, Gavin unceremoniously drops Shaun Hastings and Rebecca Crane off in California and tells them to fend for themselves. Unsure what they should actually looking for, the two wander around the American southwest for a few months (sort of like backpacking through Europe after college, but with more cactuses and Bud Light) before resolving to recover whatever information the Templars have gleaned from Desmond's body, out of respect for his father.
The search for his remains leads them to Abstergo Entertainment in Montreal, the Templars' entertainment arm that is in no way Ubisoft, where they suspect something nefarious is going on involving his genetic information. They infiltrate the organization, posing as a terrible barista and sassy delivery woman respectively, and butter up the company's antisocial head of IT to get them access to Abstergo's servers. Sounds like a solid plan, if only he wasn't playing them.
November 2013 - December 2013 - the events of Black Flag take place, everything gets weirder
While playing the research analyst in AC: Black Flag, you don't leave the Animus that often, so it can be hard to pinpoint exactly when shit hits the fan. Things look okay at first, with the Assassins granting you security clearance so you can gather intel for them (including data on Desmond's remains). However, it turns out John the IT guy has ulterior motives, and uses your hacking efforts to blackmail you with nearly fatal results.
Turns out, John is a special breed of human known as a Sage: back when humankind was still trying to parse fire and sharp sticks, Juno spliced the DNA of her late husband into their population to ensure he would be reincarnated as a human repeatedly throughout the centuries. John is one of those reincarnations, and reveals his beloved "wife" needs a body she can possess, since she was merely a spirit when she escaped and is currently floating around the fringes of the internet like a common cat video. He tries to fix the problem by turning you into an empty vessel (ahem), only to be shot down by Abstergo security and hauled off to one of the company's secret laboratories.
December 2013 - Gavin and company learn the fate of the Osaka Brotherhood
While Shaun and Rebecca deal with their Canadian comedy of errors, Gavin and his crew learn things aren't going well across the Pacific either. Discovering that the Assassin cell in Osaka, Japan has gone dark, they investigate the cell's abandoned bureau and find their brothers and sisters have been wiped out - not by Templars, but an exceptionally brutal arm of the Yakuza called the Onmoraki-Gumi. Since the leaders of the Osaka cell, Saeko and Kenichi Mochizuki, were Gavin's childhood mentors, he takes it all a bit personally.
At least, he does until he figures out what's really going on. After the Osaka bureau was destroyed and her husband killed, 78-year-old Saeko led the remaining Assassins in a vicious takedown of the Onmoraki-Gumi, assuming the gang's name and taking over all their front companies. She welcomes Gavin's team with open arms and works with him to secure regular weapons trade between her cell and Assassins in the Philippines. They don't call her 'Frightful Grandma' for nothing.
March 2014 - the Russian Assassins' horrific fate comes to light, and Gavin gets a new bodyguard
Satisfied that the Japanese Brotherhood is in good shape, Gavin and team take off again, this time headed for Moscow to find the long-silent Russian Brotherhood. They don't have to look long: as soon as they land they meet Galina Voronina (those who've played through Syndicate might remember her as Shaun's friend who likes killing things), who tells them about her clan's horrific fate. Everyone in the group was forced into a makeshift Animus by their Mentor, Galina's mother, which destroyed their minds and turned them into bloodthirsty killers. That point established, Galina's not shy about asking Gavin's crew for a favor: help her kill the twisted remains of her family.
The group agrees to lend a bloody hand, though it turns out to not be necessary - once they arrive at the Assassins' home lab in Protvino, Galina kills everyone herself, including her twin sister and the babbling shell that was once her mother (who seems to be having a chat with Juno over the airwaves just before her death). Maybe she just needed some emotional support. That abhorrent task behind her, Galina joins the Altair II crew as Gavin's personal bodyguard, and the Georgian and Japanese Assassins join forces to rebuild the Russian Brotherhood.
May 2014 - June 2014 - a spy is uncovered
Deciding that a full year without a single phone call is plenty enough time to wait, Gavin tracks William down at a secret bunker in Norway, where Rebecca and Shaun are staying as guests until that whole sided with a dangerous zealot thing blows over.
Before Gavin can give William a proper finger-wagging about pulling his own weight, Rebecca cuts the party short by revealing that there's a spy among Gavin's crew - she intercepted encrypted transcripts of their activities sent to a secret hacker collective called the Initiates, who are able to track the movements of both the Assassins and Templars without being noticed. In proper Assassin fashion, Gavin and William pull everyone aside individually and ask a couple of questions to figure out who's going to end up getting thrown overboard in cement shoes.
June 2014 - the Assassin Order gets a whole lot bigger, thanks to Shaun
Once they discover the traitors - the crew's medic and mechanic, who both believe the Initiates are a vital and trustworthy resource - Gavin orders Galina to execute them where they stand. It's okay though, because it turns out he's just having a laugh, the jerkass. The interviews were to help William get to know the crew on threat of death, and both he and Gavin think the Initiates would make a fine and rational addition to the Assassins' intelligence network, if they can be persuaded to act.
While the Initiates are at first reluctant to team up with the Assassins, wanting to maintain their anonymity, Shaun puts out a plea for help, pointing out that if they stay neutral there might not be much to be neutral about for long. The Initiates are so moved by his passion and Britishness that they agree to support the Assassin cause. That accent can move mountains.
October 2014 - The Assassins destroy the first Shroud of Eden, have to go look for another one
With the assistance of a mysterious coordinator named Bishop, hired by William to help manage the Initiates, Gavin's crew infiltrates an Abstergo lab in Paris. There, the Templars are studying a Piece of Eden called the Shroud, and/or the Golden Fleece, and/or Joseph's coat of many colors. Turns out it does something well worth writing legends about: it heals virtually any injury as long as the afflicted puts the Shroud on before death. The Templars plan to use it to recreate a Precursor body from scratch, so they can view ancient First Civilization memories and reverse engineer the Pieces of Eden (I think I'm getting a headache here). The Assassins, meanwhile, plan to steal it so their mortal enemies stay mortal.
The raid goes about as well as anyone could hope for a bunch of knife-wielding gymnasts breaking into a high-security fortress: they infiltrate the lab, things go to hell, and they have to flee for their lives after killing the head of the genome-sequencing Phoenix Project. The project head manages to survive by wearing the Shroud, but the thrashing he gets leaves it in useless tatters, forcing Abstergo to look for another one.
Late 2015 - the Assassins lose the second Shroud, and things get worse
Once again, the race is on for the Assassins to find a second Shroud before their richer enemies get their hands on it. To their credit, the Assassins put up a pretty good fight and lock the Templars in a dead heat, with both groups discovering the Shroud beneath Buckingham Palace at the same time. However, the Assassins' distinct lack of guns leaves them at a disadvantage, and while they take down some prominent members of the Templar Order in the fight, they still limp away empty-handed.
That's good news for the Templars, who have a brand new Shroud to fashion their magic god DNA. But there's one person who has a different idea in mind: Violet de Costa, one of Abstergo's highest ranking security agents (if you played Assassin's Creed Rogue, she's the woman who calls you a numbskull for no reason), who helped test the original Shroud for years by wearing it while someone shot her in the head. Abstergo's experiments are just a convenient way to pay tribute to her true master, a certain someone who will really appreciate it.