Dragonsworn is actually a legit wow rpg class:
Some people are going on about how Tinkers, Demon Hunters or Bards are the next approach but I have my own thesis for it, however instead of posting a short version I felt a longer explanation would be necessary.
This idea however does not strictly follow the RPG's version for game play mechanics reasons, it needs to be interesting, workable, and be compatible with the idea of a "Hero class" (Since there's no way this would be a normal one).
Armor Types: Plate (yes another plate class), mail, leather and cloth.
Weapon Types: Staffs/polearms/1hand mace,axe,sword (no dual wield)/shield/bow/gun/crossbow
Class Unique Mechanics: Oaths/Unique Mechanics Per Talent Tree
The Story (Long):
After the events of Cataclysm, many heroes of Azeroth were given the highest honor of the now mortal dragons (even if they have in dawn of the aspects retained their powers). They would be given the chance to become a Dragonsworn, oath bound to the four remaining aspects, though presently only three were interested in taking up the mantle, Nozdormu, Ysera and Alexstraza as Kalecgoz is too busy rebuilding the Blue Dragonflight from its crippled state.
As a Dragonsworn, your story begins in the past, taking us to events during mists of Pandaria in the heart of Northrend, whats going on after Arthas defeat and Cataclyms end? The Flights are rebuilding, and the mortal champions are tasked with aiding them in their goals.
Their plot arc begins with the character being chosen by the dragons to have an audience with their leaders alone. You are a recognized hero that has willingly put down the mantle of your previous affiliation to become one of their chosen and have been given this rare honor to prove yourself.
But, before you can, you must endure three tests from the Emerald, Bronze and Red Dragonflights each that will test how worthy you are to become one of their personal champions.
In each test you are assigned the talent tree of that corresponding class and thus it is designed as a tutorial segment to explain how each works. It also offers insightful lore into what each chosen dragon flight's oath-sworn does at their time.
You are sent to the once desolated land of Icecrown to find Tirion Fordrig, this story is designed to give us some continuation as to why Tirion returned to Azeroth and his goals there in a future expansion, to which you are tasked with relieving the Argent Crusade of its burdens in the North.
Tirion agrees but assigns the red sworn to relieve his men from their duty and help them return to the Argent Tournament grounds. Throughout the storyline you aid injured crusaders retreat, while fighting off waves of enemies (yes this is the tanking spec) and equally drive forwards to slay one of the last remaining scourge generals in the area, bringing life to this once desolate place once more.
You find that you are able to spread the influence of life to a point, then, you are halted indefinably as it appears there is something overpowering preventing you from advancing your life-giving task. When confronting Tirion he refuses to tell you what it is, only that he knows that Arthas power and the Lich Kings was so terrible, it will take years before Icecrown Citadel and the area around it can truly be healed, if it can ever be healed at all.
(This is supposed to be a tribute to Bolvar, because he was risen by the Lifebinders power as a monstrous creature between living and dead, he effectively blocks her healing magics on the land).
Having done all you can, you conclude the Reds test by bidding Tirion farewell as he prepares a fleet to sail back for the Eastern Kingdoms and a long overdue Darrowmere Forest, explaining the back story behind the events of Cataclysm and why Tirion went back.
Return to Wyrmrest:
That was strange, it almost felt as if all of that happened in the past? Wait, it did.
The Ruby Flight was testing you to show you how damaged the world is, and that it will always need champions to heal it no matter how long times of peace last, someone must be ready for war.
It is this point Nozdormu beckons and tells you to go next into the Future! Where you will be tested against a foe you did not expect...
And so, you go.
The Bronze Test:
Traveling into a portent future, you find yourself standing before Ironforge (if you're alliance) or Lordaeron (if you're horde) and each story has a branching and unique version of its events:
Ironforge appears quieter than usual, in fact, the snow appears to be little more than ash and smog, looking closer, you realize Ironforge is shattered forever, and the front gate has been beaten open.
A terrible army of black dragons awaits outside, yet curiously, they greet you, Lord/Lady of the Twilight. You're confused, and walk straight past passively before being confronted with a choice:
The Fate of King Muradin:
Moira and Falstaad slain by your orders, apparently, the remaining king of Ironforge tells you how you slaughtered everyone, you killed the alliance, you, broke all the pacts, shattered all the bonds, they underestimated you, and now he demands only that you end his suffering, so he can join his brothers and sisters in the afterlife.
Faced with choice, you can decide to kill him or spare him, the choice has no true impact as you are quickly beginning to understand this reality is not real, but it is becoming more and more clear who is responsible for it.
Then you enter your throne room, or rather, the former throne room of the three hammers, now vacant with only a twilight throne waiting, with your size perfect for the fit. Your adviser, Wrathion congratulates you on your final conquest and informs you that the time has come to eliminate all your remaining enemies, the entire alliance subject to your rule, nothing can interfere with you now.
Only then does he realize something is wrong, and shortly after, you turn to hear a familiar voice, your own.
You find a shadowy version of yourself, veiled in the void itself, consumed by the darkness of the old ones, speaking with a thousand voices. This version of you is you that could have been, ruler of all Azeroth, destroyer of worlds, domination, of life and time itself.
You broke time itself, you changed the rules, you made every enemy perish, worked your way to the top, you, abused the stream of time to become a god.
Only one object remains in your way, yourself.
In an epic conflict, you and your evil alter ego face off (be they eviler than you or simply what you might have been if you were evil) this counterpart is slain and inevitably foiled. You emerged victorious and attain a debuff "revelation" where you become aware of the consequence of tampering with time, you realize that if not used responsibly, time itself could fall apart and everything could be undone, not necessarily for the better. Tempting as it is to change the world, it is not always a good idea to try.
Mostly see above, but with obvious differences. You go into Undercity to find it claimed by the Scarlet Crusade, whom even if you are undead you appear to be in complete dominion over and thus have absolute control. Apparently your adviser is the reincarnated Mal'ganis and you have become a champion of the purest power, demonic energy and light tainted into one. You are the unstoppable fire that will purge Azeroth of enemies that threaten you. You also face a choice of executing Sylvanas by hanging or letting her go in shame.
Regardless of both situations, you return to Azeroths present, where Nozdormu simply says: "Now do you understand the danger of tampering with history? Even if the outcome benefits you, it will only bring ruin to everyone, including yourself in time."
The Emerald Plight:
Your tests completed you have only one remaining test to for fill. Ysera, offers you a rare opportunity to enter the emerald dream, and help her uncover a strange anomaly that is the Rift of Aln and its purpose.
Into the dream you go! More specifically, a segregated part of the dream which is limited to a single zone, this zone is called the heart of the Rift, where you see exactly what Ysera is referring to. A strange, endless dark pit that has a seemingly empty aura of emptiness around it. This chilling place haunts you, and you need to uncover why it exists in the dream.
You are made to aid one of Ysera's fellow Dragons in uncovering the plight, only to discover that Nightmarish energies resonate from it. You quickly feel a sense of danger from it as the Nightmare pours in a second time, invading the Dream with a vengeance. Your comrade sacrifices themselves to protect you and tells you to run, run and flee from what you are not yet ready to face!
With warning in mind, you are made to flee! Run from the darkness! You hear echoes of Yogg-Saron's puzzle box as it taunts you "run, flee, screaming into the black forest!" The Forest itself turns black, and darkness swashes the land, turning the Rift into the Black Forest predicted and awakening the Nightmare a second time.
You escape! But over the course of events you are made to do what you can to slow it, using the healing mechanics of the emerald pact to create wards and energy barriers that will thwart the nightmares advance. Eventually you with the aid of other Dreamwardens (the name of the spec) manage to hold the Nightmare in place. For now you understand there is nothing else you can do, you are not ready, you need to grow stronger, even champions have a limit to what they can do, and it falls onto you to prepare yourself for that trial ahead.
Returning to the present Ysera is waiting, noting she has been watching your actions, she commends the champion, stating: "This is wherein events must cross, past and present, some threats we must face when we are ready to face them, in the dream, we sense those threats as visions of events yet untold, the event you saw, was very much real, and one day you will return to face it, but today, you have proven yourself ready to aid our flights against all threats we face, regardless of what shape they take."
The Flights then give you the rite of blessing, and you become Dragonsworn, bound to the flights and the Wyrmrest accord, where you are tasked then to grow stronger, and represent the dragons in your respective faction in preparation of future enemies to come.
Now for the actual Mechanics:
Oaths are the Dragonsworns unique mechanic that allows a Dragonsworn to switch between buffing themselves or offering an area of effect buff that aids their allies.
This effectively makes Dragonsworn a mix of Auradin and stance swapper. Unlike say, Warriors and Death Knights however, swapping your main buff is significantly different for a Dragonsworn because it also changes what abilities you have.
The Three Paths:
A Life Guard is a Tank that uses the Red Oath to either buff their own armor or soak up damage from their allies into themselves. This swap out mechanic is mixed into the Life Guards healing abilities that are designed to keep itself alive primarily but also to draw more damage from your allies into yourself.
Abilities: (Keep in mind this is a W.I.P)
Oath of Life: The Life Guard protects themselves, gaining a 50% stamina buff, 90% armor buff and 200% aggro buff.
Bond of Life: The Life Guard protects their allies, all allies in a 50 yard radius have the damage they take reduced by 33% and an additional 33% is taken into the Life Guards own damage pool.
Titanic Strike: Using the power of creation you smite your foe for 100% weapon damage as holy damage, in addition adding an armor reduction debuff that reduces the enemies armor by 5% for 10 seconds, stacks 3 times.
Surge Of Creation: Increases healing done to you and your allies by 50% for 30 seconds.
Radiant Ward: Create a Bulwark in an area of 15 yards that draws all aggro in that area from allies to you, in addition, enemies attacking your allies will deal 40% less damage in that area.
Cleansing Breath: In a Cone the Dragonsworn breathes a flame that cleanses all curses, diseases and poisons on allies (3 min CD), in addition, enemies caught in this flame will suffer a debuff that reduces healing by 33% for 5 seconds.
A Time Walker uses ranged attacks and spells in a combination of spell casting an ranged assault to cripple your foes and leave them vulnerable for allies to finish off.
Oath Of Time: The Dragonsworn embraces the Oath of Time, increasing their attack speed by 25% their critical strike by 10% and ignoring 5% of their enemies armor at all times.
Bond Of Time: The Dragonsworn passes their benefits to their allies, increasing attack speed for all allies by 10% as well as dealing 5% more critical damage and 15% more attack power/spell power.
Chrono Shot: Strike your enemy from the future dealing 120% arcane weapon damage. A slow traveling arrow of time will fly towards your foe, if your enemy is still standing in the same AOE it will deal three times the original damage as well as the initial damage. It also damages the enemies allies for the same amount of damage if they were hit in the AOE.
Sands Of Time: Haste buff for Bronze Dragonsworn, offers the same benefit as Timewarp and Heroism/Bloodlust (Does not stack with Oath Of Time)
Temporal Distortion: Strike your foe with a bolt of temporal lightning dealing (x per level) nature damage. In addition this ability will slow your enemy each time it strikes them by 10% for 10 seconds, stacks 3 times (2.5 sec casting time with Oath active).
Accelerated Accuracy: You mark a target for you and your allies increasing critical damage dealt to that target by 10%, in addition, if the target dies while the ability is still active, everyone gains a critical strike on their next attack (lasts 30 seconds, 5 min CD).
Nether Winds: Increases movement speed by 50% for 5 seconds, (1 min CD).
A Dream Weaver uses Astral Projection to offer protection to their allies while healing them, they focus on keeping their allies out of danger more than having a heavy healing focus, thus damage resistances and damage reduction are a heavy feature of this spec.
The spec is heavily reliant on healing gear as it does low healing, but focuses instead on keeping your allies alive longer.
Oath Of Dreams: The Dragonsworn takes on the Emerald Oath, increasing healing by 50%, mana regeneration by 30% and reduces aggro by 200%
Bond Of Dreams: The Dragonsworn offers the Bond to their allies, increasing all allies healing taken by 400% and periodically regenerates allies for (x small health boost)
Woven Slumber: Puts a single target to sleep for 60 seconds, any damage taken will awaken the target.
Relaxing Spores: Applies a buff to your allies that drapes them in harmless spores, these spores heal the target for (x per level, minor) and in addition gives them a concentrated reflex buff which increases dodge by 10% for 10 seconds.
Dreamscape: Throws down an AOE field that takes your allies into the dream, anyone within this AOE takes 25% less damage and gains a 20% higher evasion chance, they also periodically regenerate (x hp per level)
Astral Protection: Creates a ward on a single target that allows them to evade the next 3 attacks, in addition healing on them is increased by 100%.
Dreamers Blessing: The Dragonsworn breathes an emerald flame in a direct line up to 10 yards, anything in that line is healed for (x hp).
Sleeping Haven: The Target is made immune to damage for 3 seconds, all aggro is taken from them to the Dragonsworn and they are periodically healed to 75% of their maximum health (10 min CD).
Awakening: Resurrect a fallen player by bringing their soul back from the dream.
Well, that's the idea, in concept, there's plenty one could suggest, add or change to it but this is my idea. While I know people are fond of DH for its archtype and Tinkers for steampunk, I don't know if they would be a reality, personally I like them both but this is my own alternative that may to some seem more tangible than others.