If your description of slash is accurate, I whipped this up in around 90 seconds... forgive the paint job:
A guildie on vent noticed it resembled a clown face, it wasn't my intention but it makes it easier to explain!
(Eyeballs are tanks, eye area are slash zones, mouth is burn victim zone, freckles are healers, stubble is melee, and his red hair is a no-go zone. The best burn victim zone is the tip of each side of the mouth, as close to brutalis as possible, between the melee and the slash groups. The pink/yellow lines are just the limits of "behind" the mob for melee attackers)