Demon Hunter, from a lore and gameplay perspective, has a lot of potential to be included in WoW. I have a cool few ideas that I'd like to share on how it could be implemented to be both fun and sticking to the book in the lore.
Class Overview
-The Demon Hunter would be a Cloth-wearing class (because there are no Cloth-class tanks and melee dps), with an emphasis on melee dps and tanking. Their resource would be either energy or fel energy, dependent on spec.
-The class would be open to selection for Blood Elves and Night Elves (for lore reasons stated below).
-The three specs would be Demonology, Swiftblade, and Immolator.
-Demonology would be the tanking spec, taking on the form of the demon within to mitigate damage and unlock fel-enhanced abilities. Seeing as this is the most well established one in the lore and in the game, little is left to the imagination as to what abilities and techniques this spec would possess. This class would use Fel Energy for their resource when in demon form. This class could use Metamorphosis indefinitely, and it would be their tanking mode.
-Swiftblade would be the 100% physical melee dps spec, relying on quick blade strikes and evading incoming blows to deal damage and survive. This spec would dual wield One-Handed Swords, Fist Weapons, and Maces. Think if a Fury Warrior could mix with a Combat Rogue, but with the ability to use Metamorphosis infrequently to empower their abilities. This spec would use energy when not in a short Metamorphosis cooldown, and Fel Energy when in it.
-Immolator is what would happen if a really really angry Fire Mage mixed with an Arms Warrior. Many of the abilities that this class uses focuses primarily on manipulating spells that you and your opponent casts. The abilities could work like spell steal, or spell reflect. Additional abilities include a sort of Mana Burn that deals damage based on how much an opponent's resource (energy, rage, etc.) is depleted, or how much health a boss has left. Relative to Swiftblate, this spec is more focused on taking down spellcasters, or the spells that melee opponents use and all the while burning them with fel fire.
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The Lore
Like Death Knights, the starting area for this class must be relevant to the expansion in which they are introduced. There must also be a compelling story in the starting zone enough to both A) allow them to seamlessly integrate into the Alliance and Horde, and B) provide enough content to fulfill ~4 experience levels starting at 55. Bear with me for this next pseudo tin-foilery and fanboying.
I should note that much of the lore surrounding Demon Hunters and the way they interact with their demons is taken from the Demon Hunter resurrection quest line in Blasted Lands (to which I initially got this idea)
The Demon Hunter starting zone would be the Well of Eternity, 10,000 years ago. You are one of two pupils under the tutelage of a Demon Hunter master (could be Illidan Stormrage or another character created for this purpose). If you pick a Night Elf, the other pupil is a High Elf, and if you choose to roll a Blood Elf the other pupil would be of the purple variety. The Master teaches you about the process of becoming a Demon Hunter, including actually sealing a demon inside oneself binding the two together to effectively fight demons.
Basically the quest lines would be you trying to defend the countryside from ever increasing numbers of demons, while also continuing your training as a Demon Hunter. While you do not have a Demon yet, there is still a need to repel these fel invaders. While questing you would be assisting both Cenarius and the Red Dragonflight in fending off the invaders.
The last and final quest chain involves the final climactic battle where you are holding the line while the portal is sealed. In one last act of sacrifice, you seal a powerful demon inside of you several seconds prior to the implosion of the Well of Eternity. This demon, when fused with you, becomes your metamorphosis. The process also taxes the body so much that you are rendered in a coma to be woken up as some Expansion relevant event wakes you up from your slumber.
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What are yall's thoughts on this?