@Parmandur:
I formerly thought Dark Sun was going to be the remaining classic setting choice, but I think Planescape is the most likely now.
Yeah, I hate to admit it, but I agree. They likely stopped working on Dark Sun when they gave up on psionics. Without a fair amount of work on those, it doesn't seem likely Dark Sun is on the way.
More groundwork has been laid for Planescape, and it continues their emphasis on the multiverse, and it's a more natural fit for post-Tasha 5E's assumptions.
Absolutely.
Dark Sun, by contrast, would require a fair number of adjustments from core assumptions (defiling magic, psionics, intentional distance from classic D&D tropes, etc.),
Defiling is easy to do. Give advantage on an attack, disadvantage on a save, or a free up cast when you defile. It doesn't need to be more complicated than that. As long as it's tempting, it'll get used. Psionics are about as done as they're going to get, I think, for this edition. They might give it another push, but their last attempt floundered. It's that last one that's the biggest hurdle. D&D + something new is fine. D&D - something old is not going to fly. 5E is not the restrictions edition. Unfortunately, Dark Sun is the restrictions setting. It basically defines it. You couldn't pull that off, not from the current design team, without undermining either the edition or the setting. WotC is clearly ready, willing, and able to undermine settings if it means catering to the wider fanbase.
and reworking the setting to eliminate those risks losing a lot of its flavor (and annoying the setting's veteran fans).
Not to put too fine a point on it, but they've made it plain that they don't care. If they can radically alter classic settings and get even a good-sized chunk of the new fanbase to buy in, that will blow the grognards out of the water every time. They don't need to cater to the old fans anymore. They haven't in years. New people will be interested in the new versions of the classic settings, and given the size of current D&D fandom, that will be more than enough.
The "revisit" is almost certainly the Forgotten Realms, just in time to tie in with the 2024 revision. It seems widely agreed that SCAG was lacking as a setting book, unlike Eberron. This "revisit" also gives them a chance to make further setting adjustments, to match post-Tasha's shifts.
That does seem the most likely. Or Greyhawk.
Both Planescape and the Realms will surely get the slipcase treatment, as you suggest, unless Spelljammer is a total bomb sales-wise.
Well, it hit #5 top seller on Amazon by Friday afternoon, so it's not likely to bomb.
As for the other settings you mentioned:
- Greyhawk would be a good setting choice for the 50th anniversary, but either way of handling it poses risks. Make it authentic to the old-school version, and you risk offending newer gamers; revise the setting for newer gamers, and you risk offending old-school fans. What I think we could see instead is something like the Dragonlance adventure - a Castle Greyhawk adventure, as you suggest, with minimal attention to the setting proper. (This is also how the well-regarded Ghosts of Saltmarsh worked for the most part, just define a small section of the setting as an adventure backdrop.)
Yeah, that does seem likely. Maybe the same treatment as Dragonlance, an adventure path and a mass battle game.
- Birthright is too obscure to make a comeback in any form. (Sorry, fans, nothing wrong with the setting but I'm just being frank.)
Well, unless you ignore the whole origin of the name and the divine right to rule angle. It's not going to fly with modern audiences at all.
- Mystara could be interesting as the focus for an adventure/mini-setting like Dragonlance, but the most recent thing it's known for now is those re-releases of the Capcom video games from years ago. Not to mention that Wizards would probably prefer folks not dig too much into some of its setting lore.
Exactly. Like Birthright, it's not likely without a radical overhaul.