one of the leaked microsoft documents had wow on the gamepass. i guess the sub will be tied to that while the expansions will be still be buy to play
When's it going on the game pass
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It'd be weird cause the game pass is cheaper than a sub.

Sub optional would be amazing as it would shut up sub number discourse forever, hopefully. F2P even moreso (and numbers would get so high that people could never bring it up again)

Amirdrassil is already considered separate to some extent from the Emerald Dream zone on the PTR. It has its own general chat channel just titled Amirdrassil, as opposed to Emerald Dream or Amirdrassil, the Dream's Hope.

ESO and Guild Wars 2 are both incredibly successful games on a B2P Model with optional Subscriptions on atleast one of them presenting almost identical offerings to the trading post (ESO.)
ESO did a massive revamp of the entire game called One Tamriel merging all the various factions into one playable game while still being separated for gameplay purposes. Ironically I believe that event was tied into the anniversary of the Elder Scrolls as a franchise.
I could totally see Blizzard;
Revamping all of the world,
Allowing cross-faction game play while still honoring the routes with PvP,
Making the game Buy to Play with an optional Subscription that gets you Tendies,
All in an attempt to capitalize on the franchise's massive anniversary coming up next year.
Honestly Blizzard seems to be learning ALOT recently from both games and I am happy about that.
Oh shit, nice. Honestly not sure if I'd play it on console but could be good for the health of the game. Also like the implication it may go free to play, but have a premium sub like ESO Plus or something. If it has some cool stuff like free tendies, xp bonuses, etc I'd still pay for it.