I made a running build for assassins. It's pretty solid imo. Can chestrun anywhere. and It can maybe even run droks (never tryed).
16 shadow arts
12 illussion
Arcane Echo
Shadow Form
Dash
Dark Escape
Illussion of Weakness
Heart of Shadow
Shadows Refugee
Optional (mostly ress sig in chest runs)
How to use: Cast illussion of weakness + shadows refuge if you come out of the portal. And just run passed easy mobs with dark escape. If you come by hard mobs. use arcane echo/shadow form/dash. If dash has ended, you got 1 second to cast the second shadow form. After that wait till Illussion of Weakness has ended, so you gain the 200 health bonus. Then if you still have a lack of health, use heart of the shadow + shadow refuge and run away.
ahh, Echo shadow form, I used a build like it in AB, attracted loads of Wammos and nukes, and sat down and watched them consantly miss me, what a fun time.