All Xbox, Xbox 360, and Xbox One games that are currently playable on Xbox One consoles will also be playable on Xbox Series X and S at launch -- except games that require Kinect.
This is according to a tweet by director of product management JasonRonald, who said that Mirosoft conducted over 500,000 hours of testing to determine this.
Previously, Microsoft had said that the next-gen consoles would be compatible with "hundreds" of Xbox 360 games, and some select franchises from the original Xbox.

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