It's a nice idea.
But - there are difficulties
Some classes have obvious rewards. Others? Not so.
And then there are classes which what story works for one...won't for others. Paladins, for example, incorporate Blood Knights and Sunwalkers. Gnome priests are actually doctors and surgeons. And so on.
The system should be set up so the instance can be used by several classes or stories. A Draenei Priest or Paladin would get a LOT more form a scenario involving (as an example) the Black Temple than a Gnome surgeon.
The scenarios themselves should be difficult, required to be done solo - and SCALE so they can't be outlevelled. And they should be relevant to the class/race taking part. A Paladin might go to Stratholme Chapel, home of the first Paladins or pay homage to Faol at the Scarelt Monastery...but a Sunwalker would need a different task.
So - rewards?
There is the usual:
Transmog weaponry and armor
Titles - Would an Alliance Warrior like to be honored by the Dwarves as a Thane?
Actual weapons -
So - Warlocks get Green Fire. Do they get to go back back to BT to learn how to summon their FelFlame steed? Learn to fly?
Other classes? Some are easy to generate rewards or stories for.
Paladins - a Libram graphic. Eyes glowing with power and a rumbling voice. A weapon appropriate to their actual side. A Golden Drake as their flying Mount. Tyraels Wings. Lightbringer title. The ability to create a Mightstone.
Hunters - there was a Draenei questline teaching you how to use three types of pet. At the end of it, the trainer held up a fourth model and put it away. What type of creature could you catch? Or maybe - train ina different fashion. Learn to ride any beast as a temporary mount?
Rogues - the Alliance has SI7. Spy stuff. That means they have a reason for the James Bond stuff and can actually be sent anywwhere. In to any existing instance or scenario. There is also Ravenholdt.
Druids - the ability to enter the Emerald Dream
Others - just a little bit harder to be imaginative.
Warriors could get their Whirlwind quests back. Priests could get Benediction. Or some sort of graphical effect.
The problem is that most classes don't really have an equivalent of green fire, something the class has wanted for a while. Paladins have their librams and the flying mount. Druids have new forms and the Emerald Dream.
Hunters would get quivers/ammo pouches shown on their back. Each rep faction would have different quiver designs.
Mages: Consumed by Energy (cosmetic buff)
Each mage class gets an animation where their feet and hands are burning with whichever type of magic they use. Also, as they walk/run their footprints burn briefly with the same energy effect.
Warriors - Carry a banner on your back, just like the blademasters and those dwarves in Twilight Highlands.
My name is Cernunnos, I will love you like no other, I have died a thousand deaths, each time I died I thought of you.
Maybe Shamans could get an Empowered Element's cosmetic buff. Can turn it on and off by visiting a person like with Jubeka.
-Lightning spells would look more like Lei-Shen's. Maybe Windfury would cause huge gusts of winds slashing/hitting the enemy when it procs.
-Flame Shock would look more flame-y. Lava Burst could literally be like a crack in the earth and a massive blast or geyser of lava would blast out of the crack. Lava lash would be similar, except for it creates a crack next to you and the lava arcs out of the ground and follows the way your weapon goes. Again, the lava would be more obvious.
- Earth... Ehhmmm. I dunno. There really isnt much to do with Earth. Maybe make it so that Earthquake causes those rock spikes, that most earth elementals in Cata used, to shoot up in the area. Earth Shield could be... uhhhhhh... maybe a big slab of rock jutting from the ground spinning around the shielded person. Earth shock could be a big boulder and dirt flying at the target. Or maybe just a rock spike, and the rock spike is electrified if it is from Elemental's Fulmination.
- Water. Water. Water. Uh... Maybe water could pool around the area that a target of your heal was standing? I really don't know about water.
Perhaps someone else could suggest an idea for Empowered Water cosmetics?
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