https://www.gamespot.com/articles/how-assassins-creed-odyssey-for-googles-project-st/1100-6462407/

Assassin's Creed Odyssey is the inaugural test-bed for Google's ambitious streaming platform, Project Stream. Now that the service has launched, we're seeing more details of just how the test is working--at least this time around.

According to an email sent to participants, Google will allow testers to play Odyssey for free until January 15, 2019. After that point, you'll lose your access and won't be able to continue your saved game. Streaming takes place right through the Chrome browser, and you can swap between computers by signing in with your Google account.