Shadow spell tank

[Caxxo]

I've got an off the top of my head idea about a shadow tank
Legendary'
Improved Shadow Form: Allows casting and channeling most spells while moving but reduces your movement speed by 50% while doing so. Reduces damage taken, scaling with spell power
Reduce damage done by 30%, 60% against players
Epic:
Improved Vampiric Embrace:
Vampiric embrace now only heals you but heals twice as much, heals from all shadow damage including AoE and also creates a shadow shield around you for 20% of the damage you took in the last 5 seconds, the shield can not exceed 10% of your HP
Improved Mind Flay:
Mind Flay now becomes Mind Sear essentially
And now two secondary epic REs that you can choose from
Improved Devouring Plague:
An enemy that has Devouring Plague has a 25% chance to spread it to another enemy and refresh the duration every time they hit you
Improved Haunt:
Shadow damage against the enemy heals for twice as much

Essentially it's a mobile squishy caster tank with a lot of self healing