Current AAA games can take at least a decade in development if no longer. For example, if a studio started working on a big project right now, it would have to be for the PlayStation 6 and the next Xbox. But, it appears, Microsoft is following a more extensive timeline for an unnamed video game sequel.

As part of the ongoing deliberations between Microsoft's proposed $70 billion Activision Blizzard purchase, a document is revealing that Microsoft is working on an unannounced sequel to an established franchise.

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Here's what the document, which was spotted by Axios' Stephen Totilo, says about the latest revelation: 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 statement reads. "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. Microsoft should go all-in on video game development and leverage its smorgasbord of first-party studios.