It's not really a "Deathstar" in the sense of overloading on huge damage hits, but the 9-tray formation of 'zerkers is pretty formidable with a Frontline Spined Thresher and the Warsprinter + Aggressive Shrieker combo.
Thanks to their white Skill modifier, on a turn with four unstable runes, Berserkers can Reform + Charge 4 or Charge 1 + Charge 4 at Init 3, or attack with Threat 4 at Init 4 and THEN Charge 4 at a target behind the blocking unit, all while being more or less immune to Immobilize stopping you thanks to Warsprinter.
Of course, these values could all be reduced to 2 or 0 on a rune flip, but Bloodfire Witch gives you a 50/50 shot at improving whatever result you get to 2 or 4. On a bad turn, with no red runes at all, it's still a fairly dangerous unit with a good dial, and being able to take the extra single re-roll as long as your enemy has a panic token is a great ability.
Ravos, as always, is a beast. As long as he has some support, he can lay down an incredible amount of wounds in a tight battlefield, or hunt down a hero and eat them alive.
Since this list is hunting for unstable runes anyway, why not throw in a Fire Rune, too? Lets the support berserkers lend some damage to the front lines.
It also occurred to me while playing this list that Cacophony Reaver would lend his Lethal ability to a Fire Rune ranged attack. Huh... going to have to try that.
Ravos the Everhungry x1 [40]
--Unique: Insatiable Hunger [3]
----------Total Unit Cost: 43
Berserkers x9 [50]
--Champion: Cacophony Reaver [6]
--Heavy: Frontline Spined Thresher [7]
--Heraldry: Warsprinter [3]
--Music: Aggressive Shrieker [5]
----------Total Unit Cost: 71
Berserkers x4 [27]
--Champion: Bloodfire Witch [5]
--Equipment: Fire Rune [7]
--Heraldry: Raven Tabards [2]
----------Total Unit Cost: 41
Flesh Rippers x2 [22]
--Unique: Dead Sprint [4]
----------Total Unit Cost: 26
Spined Threshers x1 [18]
----------Total Unit Cost: 18