Halo Wars 2 will be released on February 24, 2017, according to Microsoft, but you don't have to wait as there's a beta available to try right now.
The game is set immediately after the events of Halo 5 and offers a different take on the series' typical first-person approach. 343 Industries is taking on development of the game, though it has some assistance from The Creative Assembly who know a thing or two about real-time strategy games.
Those hoping to try the beta for themselves will have to act quick; it only runs for a week. You should also be warned that it's a hefty 13GB download, so don't expect to jump straight into the action. Once in, however, you'll be able to play the multiplayer with up to six players.
There will be a premium version of Halo Wars 2 available, which will feature a remastered edition of the original Halo Wars.