Board Thread:General Discussion/@comment-25491743-20160511172349/@comment-24228112-20160517073802

With Hades not existing anymore and the fact that after he went to Storybrooke the souls started to display some intelligence and the nature oft the river is changing, I think that it is either gonna let the souls move on, or free them and they move on their way,

That or Arthur finds a way to help them move on as its what he feels he needs to do to move on. He thinks his unfinished business is to repair the Underworld and maybe free the souls.