A cliffhanger in a paid service game?
You can't do it (obviously you can, just doesn't leave much to desire), the world doesn't stop, when a cliffhanger is done in a film the watcher is forced to wait, without any development. But in a service game, the cliff hanger happens and everyone just pretends something more important is happening elsewhere in the world.
Now let's summarise, the campaign was great, I felt the world creation was delivered perfectly. The only problem was the ending, Imagine this, Thanos gets all the infinity stones and just walks off with them... same energy.