Given what we know, let's see what kind of reasonable storyline we can make out of the "Mists of Pandaria."
In the wake of the Cataclysm, the Earthen Ring is still continuing to heal the world, even after Deathwing's defeat. The sheer amount of chaos wrought by his emergence into Azeroth wasn't really something that could simply be handled in a year or two. It's something that the Earthen Ring and the druids of Azeroth will have to address and repair for years to come.
But with all this healing of the ruined lands left behind, it's suddenly become clear to the Earthen Ring that they are only healing part of the world -- that there is an entirely unexplored portion of Azeroth that may be in just as much distress as Kalimdor and the Eastern Kingdoms.
Meanwhile, Azeroth has entered a period of brief calm between storms in the year or two following Deathwing's defeat, and the assorted races of Azeroth continue to recover from the losses shared in Cataclysm. In Theramore, Jaina Proudmoore receives a letter from Kul Tiras and realizes she hasn't checked in on her home since her father's death just after the Third War. The letter isn't a friendly missive so much as a plea for help. As an island nation, Kul Tiras was nearly destroyed by the Shattering and desperately needs her assistance (and the assistance of the Alliance in general).
The goblins of the Horde no longer have a war to produce profitable amounts of supplies for. With that in mind, many have been wondering with more frequency just what happened to the city of Undermine beneath Kezan. The underground capital was home to a large number of trade princes to various cartels and the wealthiest of goblin citizens. Come to think of it, those trade princes and wealthy citizens would be awfully pleased if they were rescued, wouldn't they? ... and possibly willing to part with large portions of their amassed wealth for that rescue.
En route to Kul Tiras and Kezan respectively, the Alliance and Horde come across a mysterious island, the likes of which has never been seen before in Azeroth's history. Even stranger are the island's inhabitants -- the reclusive pandaren, who are unsettled and uneasy after the events of the Cataclysm. They have sensed the earth has changed in irrevocable ways and are trying to discern exactly what happened with little success. Shaman and druids from both the Horde and Alliance are quick to recruit the pandaren's help in repairing the fragile state of the world.
With Deathwing's defeat, the Old Gods lost one of their strongest champions in the struggle to free themselves from their earthen prison. But they have an ace in the hole that everyone seems to have forgotten about: Queen Azshara. In her life as a kaldorei, Azshara's skills at magic rivaled that of Sargeras. As a naga empowered by the Old Gods, she is a formidable force to be reckoned with. Azshara was glimpsed briefly during Cataclysm but quickly made a retreat after taunting Malfurion Stormrage in Darkshore. And from her watery home, she watched and waited, growing angrier with every defeat.
Furious at the failure of Ragnaros' forces at Hyjal and the failure of Deathwing, Azshara is out for revenge. She dwells on thoughts of the Sundering that play over and over in her mind, thoughts of the treacherous kaldorei who destroyed the precious Well of Eternity -- and then promptly rebuilt it. Not only that, but the very magic for which the kaldorei condemned her to sleep beneath the ocean is now accepted once again in kaldorei society. Azshara's hatred now extends beyond the kaldorei to all races of Azeroth, all treacherous creatures, all practitioners of magic, all creatures who wrecked any chance of success in Hyjal will be destroyed in the wake of her masters, the Old Gods.
In the meantime, the Old Gods have been considering the actions of Azeroth's mortals and analyzing the results with renewed frustration. These creatures simply refuse to be corrupted by any standard means, despite the introduction of the Curse of Flesh. In fact, it looks as though the Curse of Flesh actually strengthened the mortals' resolve. It appears that the Titan's creations are far too strong to simply corrupt and turn against each other, despite the best efforts of the Old Gods.
The hour of Velen's prophecy draws ever nearer, and the mortals of Azeroth will have to contend with something far worse than anything they've encountered in the world to date. And this time, they don't have Aegwynn to protect them.
If any of this is remotely correct, we don't have an undersea expansion on our hands. Instead, we have an island-driven expansion generated as a result of the aftereffects of the Shattering. This makes sense, in a way.
After saving our home world from certain destruction, it'd be best to patch the thing up before venturing out into space again. And if the Old Gods attempt to resurrect the avatar of Sargeras -- well, that's bound to get the real Sargeras' attention, isn't it? And that would be an excellent lead-in to outer space adventures for the expansion after this one.
We'll just have to wait and see.
For more information on related subjects, please look at these other Know Your Lore entries:
- The War of the Ancients
- The pandaren
- The Third War
- Jaina Proudmoore
- Goblins and the Bilgewater Cartel
- The Council of Tirisfal and the last Guardian
While you don't need to have played the previous Warcraft games to enjoy World of Warcraft, a little history goes a long way toward making the game a lot more fun. Dig into even more of the lore and history behind the World of Warcraft in WoW Insider's Guide to Warcraft Lore.