As a major new update adds fresh story to Assassin's Creed Shadows, including the game's first proper dollop of Isu content, Ubisoft has defended the game's microtransactions and attempted to set expectations among long-term fans for the game's post-launch plans.

Shadows is notable among Assassin's Creed entries for featuring next to no mention of the Isu, the franchise's mysterious precursor race who pop up in pretty much every game (and who played a huge role in the story of the preceeding Assassin's Creed Valhalla). Instead, Shadows is a different beast — treating its Japanese setting with an unusually straight face, and avoiding anything in its core narrative that's too sci-fi or mythological.

But, finally, a new quest changes all that. Available now in-game, players can pick up the fresh story chapter A Puzzlement, which sees heroes Naoe and Yasuke meet up again with a pair of poachers (you'll have forgotten about them, but they were in the game's intro). Interestingly, new players will have this quest inserted into the game's flow early on, as it also helps better flesh out Naoe and Yasuke's relationship.

A Puzzlement is designed as a fun extra story with Naoe and Yasuke learning more about each other (and in a nice touch, completing the quest will unlock a fresh skill for each character based on the other's abilities). But the new mission will also set players on a much longer path — one that will see them, many hours later, opening up a mysterious Isu door and exploring a secret vault within.

Assassin's Creed lore fans have long been awaiting the addition of Isu content into the game, but Ubisoft has notably decided to set expectations of what this vault actually holds — without spoiling its contents directly. (If you really want to know, well, we'll get into all that further below.)

"Don't expect a full Isu Temple and a crazy two hours adventure in here," Assassin's Creed Shadows associate game director Simon Lemay-Comtois told Access the Animus. "That's not what it is. It's a vault that you need to open and there's some cool stuff and reveals in it.

"It's not side content, but it's deep lore for people who appreciate that content," he continued, stressing that A Puzzlement's story chapter featuring Naoe, Yasuke and the poachers was intended as "the main event."

Following the launch of its first paid expansion Claws of Awaji, Assassin's Creed Shadows has returned to offering monthly free updates that have offered a mix of additional quests and quality-of-life changes, as well as new crossover events such as this week's other big addition — an Attack on Titan crossover.

At the same time, Shadows' in-game store has been kept topped up with optional cosmetic items, something that Assassin's Creed has offered for almost a decade, but some fans continue to criticize in a full-priced game.

"Microtransactions, for all the flak it gets, it allows us to do the Isu stuff, the quest stuff, the parkour updates, all of it," Lemay-Comtois said, arguing that post-launch support for Shadows required some level of ongoing funding.

Intriguingly, the developer also confirmed the decision to belatedly add Isu content into the game was not something that had always been on the cards. "Oh, yeah. It's a post-launch decision," Lemay-Comtois added. "Soon as no one's looking, I'm putting Isu in the game."

So, what does that Isu cave contain? For those who don't want to spend dozens of hours trekking across Shadows' map finding hidden glyphs in order to unlock its secrets, well, the answer to it all is of course already up on YouTube — or we'll get into the details below.

Warning! Spoilers for Assassin's Creed Shadows' new Isu content follow.

As Lemay-Comtois stated, the Isu cave is indeed just a small location, though it provides fresh First Civilization weaponry for both Naoe and Yasuke (a tanto dagger and a naginata) in chests.

The cave is clearly Isu in origin, with the race's familiar glowing technology running through its walls. But, more excitingly for fans, the cave has been used far more recently — by immortal Assassin's Creed Odyssey heroine Kassandra. Various weapons and objects from her Greek home country can be seen, as well as what looks like an Egyptian item.

Most obviously, the cave is filled by a giant statue of Kassandra (it's a bit weird she had that made, but sure) which you can add to your Shadows hideout. And among the notes from Kassandra you can read, there's also one new dialogue line — which plays as a surprise to Naoe/Yasuke as they leave the cave. Is this a tease for more Kassandra in the future? The fan-favorite did return in Valhalla in a major post-launch quest, after all. Or, perhaps, this is designed as Shadows' equivalent. Time will tell.

In the meantime, Assassin's Creed Shadows is currently half price in Amazon's Black Friday sale. And in other news, the co-star of Netflix's upcoming live-action Assassin's Creed TV series has reportedly been revealed, with British-born Australian actor Toby Wallace set to play an unnamed Italian character.

If you're hunting for the best offers this week, we're actively rounding up the strongest Black Friday deals on video games, tech, and more. You can find all our top picks and price drops in our full Black Friday hub, or check out our relevant pages for PlayStation, Nintendo, and Xbox deals.

Tom Phillips is IGN's News Editor. You can reach Tom at [email protected] or find him on Bluesky @tomphillipseg.bsky.social