Over their past few releases, Ubisoft have embraced cooperative multiplayer. It all began with Far Cry 4 though, which allowed players to buddy up with another friend to roam the mountains of Kyrat and take part in a small pool of side activities. While the co-op implementation was a little rudimentary and limited in that title though, Ubisoft is giving players total freedom to play through Far Cry 5 with another person.
While you can still use A.I. teammates to replace real-life companions, more often than not they're only going to get in the way rather than help. Instead, you want to be teaming up with an actual person, clearing out cult-infested hideouts with one of you on the ground, and the other providing overwatch in a plane.
Far Cry's sandbox comes to life when it's shared with other people, and flying through the countryside while blowing away goons on quad bikes with your best friend by your side is what gaming was made for.