Valve and Microsoft made a startling announcement recently, confirming that four of Valve’s popular titles are now available as backwards compatible titles for the Xbox One. What’s more is that each of the four games have also received Xbox One X enhancements so that you can play them in native 4K ultra high definition.

Over on the Xbox Wire it was revealed that the four games, including everything packaged within The Orange Box, are currently available as backwards compatible titles for the Xbox One.

As mentioned on the page, the four Xbox One X enhanced titles join the 17 other already enhanced backwards compatible games, so now there are a total of 21 Xbox One X enhanced backwards compatible games available…

“Xbox 360 games enhanced for Xbox One X run at a higher resolution and 9X the original pixel count. The power of Xbox One X enables the Xbox 360 emulator to showcase the very best version possible with the existing assets—all without touching the game code. Today’s additions join the 17 previously released enhanced Xbox 360 titles like Red Dead Redemption and Skate 3 for a total of 21 Xbox One X Enhanced Xbox 360 games.”

Technically this includes more than four games considering that the Orange Box also comes with Team Fortress 2, so you actually give five games in one.

The Half-Life 2 package also comes with Half-Life 2: Episode One and Half-Life 2: Episode Two.

This comes shortly on the heels of Crytek enabling the Crysis trilogy to run as backwards compatible titles on the Xbox One as well. They obviously pale in comparison to the highly lauded original release on PC, but if you missed out on Crysis last gen and you have an Xbox One, you can grab the three games right now along with Valve’s cache of seventh-gen first-person shooter games right now.

If you have the physical discs you can install them onto your Xbox One hard drive, or if you purchased the games digitally, you can install them from your Xbox Live account.