Xbox working on mystery game that could take 10 years to develop

According to Microsoft, an in-development game at the company could take an entire decade to develop.
Via an amended complaint in a lawsuit in relation to Microsoft’s attempted takeover of Activision-Blizzard, some interesting details have been revealed, first spotted by Axios’ Stephen Totilo.
“Halo Infinite, a recent title from Microsoft’s first-party Halo franchise, was in production [REDACTED], and cost almost [REDACTED] million to develop and bring to market,” the complaint reads, continuing, “Other Triple-A games take even longer to develop. For instance, according to one Microsoft executive, [REDACTED], a forthcoming title from the [REDACTED] franchise, may take a decade to develop.”
Of course, lawyers at Microsoft have access to private information, so the details here have been since redacted for their release to the public. Still, there is at least one very good guess as to what this mystery game with a possibly decade-long development cycle may turn out to be: Bethesda’s Elder Scrolls VI. Considering Bethesda is now part of the Xbox family since its acquisition and considering Bethesda’s famously long development cycles, the next Elder Scrolls game taking a full decade to develop could well make a lot of sense.
However, this is also an interesting assertion when it comes from Microsoft. In most cases, games are developed in around 3 to 5 years, and development cycles that take 10 years or longer usually mean there are management troubles, issues with development, or could be coming from a smaller studio without the resources to channel directly into a single project for an extended period of time. Accordingly, it’s interesting to hear directly from Microsoft that the company is already planning on a possibly decade-long developmental cycle for a game.
As of now, this is all just speculation. And furthermore, while a game may take a decade to develop, it could conceivably also not take that long, either. It could also be the case the game in question is not an Elder Scrolls game; however, for all the Elder Scrolls fans out there, we wouldn’t expect Elder Scrolls VI to drop anytime soon, either way.