TLDR - What cool new weapons, magic, and technology could the various races of WoW have in the future?
At the end of 5.2, both factions got a new source of power, a kind of 'upgrade' - the Alliance captured the Titan-energy known as 'Vita' from the Thunder King, which was infused into Jaina's staff, while the Horde seized the 'Anima,' another type of Titan-energy that the mogu used in their flesh-shaping experiments, together with mogu Anima-powered golem technology, all of which was claimed by the blood elves.
Now, at the time people speculated if either of these prizes would be employed during the Siege of Orgrimmar, but so far there don't seem to be any great sign of them - the soundfiles don't indicate Jaina raining down Vita-lightning destruction, and there's no mention of blood golem armies or Anima-infused arcane sentries.
Which is a bummer!
But it was still rad that each faction got some new weapons to play with, and a running theme throughout the expansion has been Garrosh's Horde 'teching up' and acquiring new toys to play with, from the war machines that goblins have been building to ancient weapons of mass destruction like the Focusing Iris, the Divine Bell, and the Heart of Y'Shaarj. And even though all that cool stuff is going to get wrecked up by the players, it got me thinking of ways that the player factions could tech up - an arms race of sorts, with new technology, knowledge, and power being brought in from all the races as they spread throughout the world, uncover Azeroth's secrets, and create brand new weapons of their own.
So what follows is a brief run-down of some possible stuff each race could bring to the battlefield in the future. Feel free to comment, throw out ideas, and speculate about what other new advancements could be brought to the factions.
-With Anduin's exploits becoming widely known, there is a surge in worship of the Light. The Church of the Light membership swells. Many new paladins, crusaders, and clerics are trained. An order of Light Monks is founded based on the learned principles of the August Celestials combined with the Light.
-Dalaran rejoins the Alliance. The Thunder King's power, the Titan energy known as 'Vita' is studied in the city as a power source (together with dwarves who have learned much from Titan holdings). 'Thunder Magi' train to utilize it. The resources of the magical city are deploy throughout the Alliance, leading to more mages. Neptulon's absence allows greater dominion over water elementals, and many more of them are brought forth to serve the Alliance.
-Many blue dragons join Dalaran and the Alliance. The Spire Needle and other blue dragon magi-tech is employed to utilize Azeroth's ley lines to a greater extent. Weaponized Spire Needles act as mobile 'tesla coil' cannons, blasting enemies with arc-lightning.
-Dark Irons share the full extent of their technology - golem construction, binding hostile elementals, deep earth mining drils etc. Dark Irons combine their art with Bronzebeard steam engine technology to create new war machines - dark iron steam tanks, elementals bound into war engines. An elite brotherhood emerges - High-tech dwarven shock troopers with ranged weapons, steam-powered armor, etc.
-Bronzebeard dwarves expand their knowledge of Titan technology - work with Dalaran to create 'Vita' powered constructs. Prototype Titan creation engine to bring forth giants of living stone - a limited run of Watcher-type constructs who are born with vast knowledge and give aid to the dwarves.
-Wildhammer shaman grow stronger, building new storm-hammer style weapons (storm-lance, storm-axe, etc) with dwarven 'Vita' power. New breeds of gryphon are brought forth, including giant gryphons. New types of beasts are tamed - giant storm eagles, great northern criosphinx, etc.
-Dwarves have strong bonds with Earthen, Tol'vir, and the northrend giant races. Knowledge flows freely from Titan holdings in Ulduar and Uldum. Titan watchers Mimiron and Thorim provide guidance and support.
-Gnomeregan is finally taken/cleansed/restored with new technology and new knowledge of the Light. Advanced technology is implemented, developed from Titan tech found in Ulduar and Uldum. New machines and constructs roll off the assembly lines.
-'Vita' power fully resurrects Gnomeregan's industry.
-Conquering the Firelands has wrought an astounding change. The connection between Mount Hyjal and the Firelands has become stronger, transforming the Firelands from a flame-blasted wasteland into an elemental forest - blackwood trees with leaves made of flickering flames grow throughout the Firelands, and animals of living flame populate the abundant growth. The element of flame grows closer to its nature as a source of energy, the energy of life that animates living creatures, rather than a force of destruction.
-The energy of the living flame of the Firelands catalyzes astounding growth throughout Mount Hyjal - wildgrowth becomes rampant all throughout the woodlands surrounding Hyjal. Treants grow at a much faster rate - the ranks of the treefolk swell. In light of the Horde's recent slash and burn efforts, many treants re-affirm their ancient oaths of alliegance with the night elves.
-Night elves grow closer to their allies in nature - the mountain giants, the beasts of Kalimdor, etc. New beasts are tamed - manticore, gorgon.
-Druids expand their powers, exploring new forms - serpent, turtle, scorpion, crocolisk, toad, etc. More animal ancients called forth from the Dream to teach new abilities. Aid from the green dragonflight.
-The Exodar is restored - becomes mobile across all Azeroth. Unites with Tempest Keep, which was recovered by the Naaru from Outland. Tempest Keep becomes a place of learning and teaching the ways of the Light - races from all Azeroth flock to it.
-Draenei produce more weaponry using naaru crystal magi-tech - artillery guns, flying discs and chariots, golem constructs
-Reunited with the naaru and Tempest Keep, the Draenei can bring in allies they encountered in their travels across the universe - auxilliary forces from any number of brand new races.
-Gilneas is retaken. A societal divide occurs - worgen who wish to resume their former lives as humans repress their wolf nature. They make use of more advance victorean era technology and have a more 'refined' society, where worgen transformation is frowned upon. As a consequence, some who cannot fully control their wolf-side suffer from the repression - they form bloodthirsty secret societies and wolf cuts. Some mutate into different forms - full wolf form, huge 'alpha' worgen giants, etc.
-Other worgen try to live a more balanced existence, allowing their wolf side greater freedom and thus keeping their darker urges from overwhelming them. They become closer to the night elf way of living, draw more allies from the Dream and animal demigods, etc.
-I would be super stoked if the Heart of Y'Shaarj could stick around and be used as a power source. Also, the black blood of Y'Shaarj could likely be made into a metal, like saronite, and used to create awesome weapons. Plus it'd keep the mantid in line. But, that's obviously not going to happen. Oh well!
-Some orcs continue to develop industry, exploit resources, and develop war engineering as they did under the True Horde. Some of Garrosh's innovations and war designs are too useful and powerful to completely discard.
-Major push-back against ravaging nature, resurgence of shamanism. Orcs have much ground to regain with the elements.
-New war beasts remain with the Horde - magnataur, proto-drakes, direhorns, devilsaurs, etc.
-After their significant losses, some zandalari and trolls from other tribes petition the Darkspear for entry to the Horde.
-Farakki, Drakkari, and Gurubashi trolls bring new shamanistic techniques to the Horde. Zandalari bring new arcane magic.
-New troll warbeasts become more widely accepted. Pteradons, direhorns, thunder lizards, etc.
-Trolls begin to employ the loa more widely as all the tribes pool their resources, creating loa-powered constructs, summoning monsters, harnessing the dead into temporary shells to revive powerful warriors from the past, etc. Voodoo magi-tech using loa-powered stone 'machines.'
-The powers of the sunwalkers are developed further.
-Druid lore expanded, loa-style spirits from the tauren perspective (nature and earth spirits, etc.)
-Forsaken push their engineering, alchemy, and science-based necromancy. Necrotech faction - using technology combined with reanimated flesh. More frakenstein and zombie undead, less ghosts and spirits undead.
-Val'kyr are harnessed into huge necrotech engines that speed up resurrection. Lots of spooky lightning, glowing green slime, and the wailing of the damned. Val'kyr are super bummed about it.
-Forsaken spies stole mogu Flesh-Crafting secrets and arcane relics, and they are being adapted to Forsaken necrotech for crafting new types of abominations.
-Blight production continues in secret. New applications are developed for creating deadlier war beasts and monsters, as well as powering war machines.
-The Titan power of 'Anima' was captured from the mogu. Blood golem techniques have improved bloof elf golem crafting immensely.
-Anima is formed into crystals, augmenting blood elf crystaltech. Crystals are being used to harness all manner of energies - the Light, the Void, arcane, flames, fel energies, etc.) Manabomb development continued in utmost secrecy.
-Divide between blood elves who employ mostly arcane and magi-tech, and 'sun' elves that are starting to use more of the Light from the Sunwell - greater numbers of priests and paladins.
-'Sun' elves employ more beast allies - hawkstriders, dragonhawks, pheonixes (new types - flame, frost, frostfire, lightning, etc.), new types of avian creatures
-Goblins continue developing their crazy engineering, natch.
-Goblins explore blending elemental power with their engineering, binding elementals into war engines and mechanisms.
-Mogu life-shaping techniques are used, augmenting goblin alchemy and what they already do with their hobgoblins. Many new and terrible creatures are developed, spliced with technology, etc.
-Goblins begin excavating ancient goblin technology that was unearthed by the Cataclysm. This tech was created when the goblin ancients had their intellect greatly augmented with the mineral kaja'mite. When the ancients ran out, they sealed their machines away because they knew they would soon lose the intellect and reason to employ them safely. Modern goblins are digging them up and experimenting with restoring them - they're sure everything will be fine, they know what they're doing, don't worry about it, what's this button do, uh-oh...
Can't really think of anything offhand that the pandaren could bring - maybe the life-giving waters of the eternal vale (if it's ever restored) will give an advantage to those who employ them. They can grow massive amounts of food, or be abused to aid in life-shaping and breeding giant war-beasts (maybe).
So, there are some of my ideas of how races could develop their war technology in the future. Their war... craft, if you will.