Board Thread:General Discussion/@comment-30664268-20170429210906/@comment-13682699-20170522021147

There is a very popular fanfiction on Ao3 that very aptly describes a scenario as to what would happen if you did bring him back before you left with everyone.

Its called One by One by the author CourierNew. Its very descriptive and is one of the few ways I can think of how a Saved Asriel ending would go.