During a recent event dedicated to Halo Wars 2 at PAX West 2016, 343 Industries' game director Dan Ayoub briefly discussed an entirely new mode for the upcoming Halo-themed RTS, which will be focussed around short game sessions.
"One of the modes, which I can only tease for the time being, is actually a completely new way to play a RTS. It really takes standard RTS gameplay and turns it on its head. And that's a mode that can be played in a shorter time frame as well, like five, six, seven minutes".
Unfortunately, Ayoub gave no further details about this mode, but it is very likely that we will know more about it in the coming months. Halo Wars 2 will debut on February 21, 2017 on PC and Xbox One, but a second beta test has been announced and it will be available in the weeks prior to the launch.