Ok, I've had my fun teasing
Here's the build I use: OgdTkY285RnxDzGpZcXswY0KAA
16 Earth, 12 Shadow Arts, 4 Energy Storage.
It's fairly simple but timing can be awkward.
Start the Nolani Academy mission and run to the lever. The Charr, including a boss, will begin running towards the portcullis so cast Glyph of Elemental Power, Shadow Form then use Death's Charge to get to the boss.
When you're beside the boss, cast Sliver Armor, Ward Against Foes then Grasping Earth to prevent them running to away. 75%+ of the time the boss will die so ou can re-cast Sliver and Shadow Form then rinse, lather and repeat.
Dying is inevitible and don't expect to kill everyhting. Just keep going in the mission over and over and enjoy the golds, max Tribal Axes and Sickles.
Warning: Nerf Imminent
Feast on this for 2 mins work: