"Most critically, none of these actions can harm other players. Even movement can’t be used as a weapon; players simply pass through each other, making it impossible to bump other players off a high ledge or otherwise perturb their progress. Movement can’t even be used to race ahead and steal a desirable in-game item before another player can get to it, because power-ups are not consumed when acquired: they remain in place for future players to receive.
All of this may sound like it stops just short of banning communication entirely. Will players even bother to interact with each other? Surely, such a limited palette of options will render the multiplayer aspects of Journey trite and inconsequential.
But that’s not what happens at all. Instead, Journey players find themselves having some of the most meaningful and emotionally engaging multiplayer experiences of their lives. How is this possible?”