User blog comment:Varadu/Expansion after Legion/@comment-7263041-20160523050846

We still have to deal with Queen Azshara and N'zoth on Azeroth, and then of course we have multiple Legion worlds that we can head to including Argus.

The ultimate end-goal seems to be that we'll end up fighting against the Void Lords as part of the Army of Light, but what happens going forward remains to be seen.

As far as artifacts go, I don't think Blizzard can go back to normal weapons after Legion. They may give us new artifacts that fit the expansion we're going into, or they may simply turn the artifacts into a new form of horizontal progression, give us new pages of traits as we level along with new apperances etc etc.