Shaman Karrakh quest chain..?! (Spoilers)

[Vulture]

At lvl 18 you should have gotten The Reaper eternities ago to use Time Back to restore your Demons' casualties instead of sacrifice.

Turn 1 -> activate run and move Demons across the field one tile shorter than they can, drop pentagram. Use ranged to kill enemy ranged, cast target if neccessary. Bring in your melee strikers half the way and pause them. Enemy moves and eats infinite retaliation from the Demons. Your strikers move last and finish off what's still standing.

Turn 2 -> Drop the Demons' minions and hope they're Demons, too. Pause any of your troops so you have the last action in this turn. Your strikers kill stuff, you cast whatever you want. Enemy moves and eats retaliation yet again. It's your paused unit's turn now: cast Time Back on Demons. Demons are fully restored. What's left on the battlefield should be so decimated now that nothing is a threat to you anymore.

Result: no losses, and you have surplus rage from killing leftovers which you can take to the next combat. See also: chain fighting (search function).