Four classic Valve games return to the Xbox as part of the Xbox backward compatibility program. Not only that, but Half-Life 2: The Orange Box, Portal: Still Alive, Left 4 Dead, and Left 4 Dead 2 are Xbox One X enhanced.
Four classic Valve games, three of which part of the classic Orange Box, are now available on the Xbox One and Xbox One X through backwards compatibility. If you haven't yet played any of these games they are certainly worth it, especially the first-person puzzle platformer Portal.
Other games from Valve available today include the modern classic Half-Life 2, and the two co-op zombie games Left 4 Dead and Left 4 Dead 2 which pits up to four players against a horde of zombies as they fight to survive.
Xbox backwards compatibility continues to be a killer service for the platform. As more and more games become locked away to previous generations the openness in the Xbox system is proving to be a good deal for gamers who might have a backlog of games from previous generations.