According to a listing on the Xbox Store, the original "Halo Wars" game appears to be coming to Windows 10 PC. Supposedly the original "HW" game by Ensemble Studios will be part of the "Halo Wars 2" Ultimate Edition bundle.
The "Halo Wars 2" Ultimate Edition will retail with the Season Pass and other additional extras. However, the inclusion of the original "Halo Wars" - as "Halo Wars: Definitive Edition" - is what is most interesting.
Microsoft's Xbox Play Anywhere program, announced at the E3 2016, provides the ability to buy a game for either Xbox One or Windows 10 and have it automatically available on the other platform. With this, "Halo Wars Definitive Edition" would be available for Windows 10 as part of the Ultimate Edition.
The original "Halo Wars" was released only for the Xbox 360. Recently Microsoft allowed "Halo Wars" to run on Xbox One via backwards compatibility.
Kotaku points out that as RTS entries in Microsoft's flagship franchise, a PC release for the original "Halo Wars" was notably absent. This is a peculiarity for a platform that is considered the home of RTS games.
However according to the XBox Store listing for "Halo Wars 2: Ultimate Edition," "Halo Wars: Definitive Edition" will be a newly re-mastered version of the original game. "Halo Wars: Definitive Edition" would be running natively on both Xbox One and Windows 10.
"Halo Wars: Definitive Edition is an enhanced version of the original "HW." "Halo Wars: Definitive Edition" includes improved graphics and all the DLCs created for the classic real-time strategy game.
This far, "Halo Wars: Definitive Edition" will only be initially available as part of the "Halo Wars 2" Ultimate Edition package, but separate availability of the remastered original later on would not be surprising. "Halo Wars 2" is scheduled for release on Xbox One and Windows 10 PCs on February 17th 2017.