Have you free skillpoints to spend ?
Have you ever tried to upgrade the Summon Ghost skill?
Or the skill "Healing" (2 or 3 points, or more) ?
Combine this with Hide in Shadows (1 point is already useful).
Summon you Creature, go into the fight, then jump/roll/run away a bit, use Hide in Shadows, use Healing (you remains invisible!) and while you're invisible you can (maybe) run further away and hide behind a rock or ... use again Healing (since the Healing skill has a short cooldown time, shorter than Hide in Shadows has).
If you've problems with melee fighters like the Black Rings, take Firewall to burn more than one in the same time ...
... or take Stun Arrows to stop the Healer for an time period (for example). If you first shoot a Stun Arrow, jump in (it can be FAST with a point in Rush Attack!), use Firewall and jump back out ...
Just some strategic steps to help you finding ways, combine skills, etc ....
I've found already many good combinations, even some funny ones
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