Why not?
Blizzard does not like people datamining spoilers in PTR. It even made an effort to fight it in 8.2.5.
Leaving people in the dark until Blizzcon increases interest in the announcements and panels there.
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Such type of content does not need to be linked to classes.
Whatever...
Apologies if this is just a lot of repeated theories, I've been busy since 8.0 speculation wandering the lands of DMCAs Azeroth.
My speculation: Nyalotha and Plunder Isles in 8.3. And I think the Old God/N'zoth thread will pretty much be over and fade into the background with lingering implications, just like Bolvar and the Scourge.
Maybe they'll push Plunder Isle to 8.3.5 to give us something fun to cleanse our palettes from the horrors of war.
My prediction is 9.0 will have nothing to do with Shadowlands, Old Gods, Black Empire, etc.
I feel like there's a lot of small details pointing to the infamous archipelago, the Dragon Isles.
Random quest in Drustvar with the Red Dragon really reminded me of the shipwreck survivor quest in Azsuna in Legion. Then we have all the dragon focus and updates throughout the Essence system, which I think is interesting because the Essence system is a pretty recently developed band-aid made to fix the Heart of Azeroth system everyone despised, and wasn't really planned out from the beginning.
We've seen cash shop mounts be predicative of future expacs before, sometimes subtly, such as the Heart of the Aspects being the eastern dragon animation rig for the then in production Thunder Serpents, so a new dragon mount seems interesting when put in comparison to other little things mentioned above.
Then we had the Black Dragon Scale quest in the Island Expedition, with our first ever official mention of the Dragon Isles from the Blacktalon NPC. We already know Wrathion was up to something back in Legion with the Death of Chromie scenario, and then again the Blacktalon Watcher showing up in the Essence scenario with Ebonhorn and the several ones you can find in Nazjatar. And now the dragonman himself is showing up in 8.2.5.
And of course, the Void Dragon model.
Coming off of the 15th Anniversary and Classic and Reforged, I predict the Dragon Isles will be a concerted effort to return to the original mystique and "land of mystery" vibes the vanilla held, and will attempt to be evocative of that.
Of course, it can always just be coincidence, these are just my predictions
8.3 will definitely drop in December-Janurary which spoils the ending of the expansion with the expansion announcement.
"You know you that bitch when you cause all this conversation."
In the Alpha, concept art depicted Old-God Themed temple where we were meant to fight Naga, yes, but there has never been any established lore or official transcription to what the islands are. They have not officially existed until mentioned by the Blacktalon Watcher.
You cannot expect the Dragon Isles to be beholden to concept from vanilla's development when locations such as the Broken Isles, which actually appeared in previous games are not. Ulduar was a gigantic continent south of Kalimdor in this same period of development and showed up quite different when it finally made it's appearance in Wrath.
I think that 8.3 will be big in terms of systems and how it will pave the way for 9.0, but I don't expect another large landmass to come from it. Maybe something Timless isle size at best. Blizz has not made two large zones in the same expansion post launch.
Not really, half a year is the usual lasting time of a mid expansion tier.
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The Silithus leak makes sense in this case. Not necessarily the leak itself but that the final stage of the battle happens in Silithus. They could rework the zone a bit more and reuse many raid assets (AQ in HD, Heart Chamber, Titan vaults etc) and make it 8.3. End it where it began.
MAGA - Make Alliance Great Again
If 8.3 is scheduled for December, PTR must be up in October. But 8.2.5 is almost 100% after Brewfest (they put Brewfest changes in 8.2), so it most likely launch mid October. In this case 8.3 is January-February.
And it's kinda my dream - 8.3 early 2020 and expansion launch in November. I hate that Legion, Bfa and now Classic start late Summer. WoD launch date was perfect (if only launch wasn't so broken...).
Who knows we may even could see 8.3 revealed alongside 9.0, but stream in October is more likely. It would shift interest from Classic to retail and increase hype for Blizzcon.
Btw, I don't remember that Blizzcon '17 mount were datamined in 7.3.2 PTR at all if I remember correctly.