Sorry, can't find that video.
During Google's Stadia press conference, the publisher revealed Gylt, a horror game by Tequila Works, who previously developed the somber puzzle game Rime.
On Gylt's official website, Tequila Works invites you to experience a "journey where you face your worst fears and are confronted with the emotional impact of your actions."
According to the website, you will "hide from terrible creatures or confront them as you find your way through the challenges of this wicked world." This seems to suggest that the game will be a puzzle/stealth game, and the trailer seems to support that, but we'll have to wait for more details to find out.
Gylt is only currently announced for Google Stadia, within the platform's launch window in November.
For more on Google Stadia's lineup, check out every game currently announced for the platform at launch.