OK so hear me out on this because I honestly see this all happening by the end of Shadowlands.
I have a funny feeling that by the end of the expansion we are going to see Tyrande turn into a raid boss and Anduin either turn into a raid boss too or end up dying somehow. This may seem a little far fetched and quite frankly will probably piss off quite a few Alliance fanboiz but I see the writing on the wall here that's been developing since the last year of BFA.
Tyrande the Raid Boss Reasons for this?
Tyrande has growing anger and darkness in her since she has been given the Night Warrior powers during BFA. Jaina commented on this during the Maw intro scenario when Darion asked her if she saw Tyrande (her exact words were "I fear it may be growing beyond her ability to contain it"). She is overwhelmed with seeking vengeance from Sylvanas that she blindly leapt into the ground portal proclaiming that she was going to put an end to Sylvanas. We have been all over Shadowlands and the Maw yet have seen no trace of Tyrande at all. Could this be because her burning hatred has maddened her even more that she has turned to The Jailer to put an end to Sylvanas without Sylvanas knowing about it? He descent into madness started long before she even got her Night Warrior powers. The whole reason why she even has them is because of her descent. The fight with Nathanos during the pre-launch event is proof of how bad it has gotten. I have a suspecison that what may happen during the Shadowlands storyline is Tyrande somehow makes it into where Anduin is being held, he tells her how he is trying to convince Sylvanas to give herself up/turn good/whatever, and Tyrande gets enthralled by his reasoning and kills him for siding with Sylvanas. This would hold the "dying somehow" prediction I'll explain below. Sylvanas seeing how mad Tyrande has turned and starts her arc of redemption which enrages Tyrande to join forces with The Jailer to wipe out Sylvanas and anyone who tries to help her including any of the Alliance that she now sees as enemies for siding with her sworn enemy. Enter the Tyrande as a raid boss in the raid we end up fighting The Jailer. Another option for why we haven't seen Tyrande so far after she jumped into the Maw is because The Jailer and/or Sylvanas has already met up with her and turned her into a "bad guy" which feeds right into her becoming a raid boss we'll have to fight in the raid with The Jailer.
Anduin dying (more likely) or becoming a raid boss (less likely) Reason for this?
There are several things that has been said during the scenes between Anduin and Sylvanas in Shadowlands that has got me thinking that he's either going to end up dead somehow or turned into a raid boss (and dies which still leads to him being dead by the end of Shadowlands). The whole "weapon" reference has been made many times between Sylvanas and The Jailer and we all know that "weapon" is Anduin in some form. Whether this is him being corrupted or killed or what, the pieces have been placed that hint that he will be used as some instrument of destruction as a "weapon" against someone or some thing. This could mean a few things. One could be that The Jailer and Sylvanas use him against US in the raid where we fight The Jailer (which would see a fight against Sylvanas too possibly). This could be a stand alone fight against the weaponized Anduin or him being part of The Jailer fight instead. The other possibility is that when The Jailer and Sylvanas turn Anduin into this "weapon", seeing his transformation gives Sylvanas a change of heart to see how deeply evil The Jailer's plans are and thus begins her arc of redemption where she helps us and the covenants bring an end to The Jailer (strong possibility). Now the other part of my claim. If Anduin doesn't become a raid boss, the time until his death is ticking closer and closer as more and more cinematics are released by Blizzard. The first one was in No More Secrets No More Lies when Sylvanas brings up to Anduin how he comes from a long line of inevitable fate of Wrynn's early demises in an endless war because they all have died too fighting a war. Since that cutscene forward, all of her interactions with hints at his demise in some way when she says join us willingly (submits to being turned into a weapon) or be made to serve (be killed and raised as a weapon).
What are your thoughts? I call it now, Tuesday January 5th 2021, that these things will happen some time during Shadowlands.