Looks super op to me. You'll have to give him a super low health pool to accommodate his trait. And the cooldown on E is unreasonably low.

Trait is same as Xul?

I think that the Trait is a really cool idea. However, it's extremely over powered. Making a hero 30% vulnerable, or healing yourself for 20% max health per second is insane. You need to take those numbers down to 1%. And make the healing per hit, not per second. Also don't let basic abilities add stacks, and stacks should reset if you switch between dmg/heal. The Q and W abilities are very generic and boring. I know that those are her original skills from D2, but maybe you should...