It's currently free on the US microsoft store for the Xbox One. I have read it may be a part of the free weekend but there are posts online saying you can just download it and it's yours to keep. Might be a pricing error.
I just signed in to my AUS account and it appears to have worked too. I don't even own an Xbone.
Mod 28/10: The bundle is free for the weekend only, multiplayer is also free for non gold members.