Scarn is the final boss of Darkening Deeps and only available in expert difficulty. Scarn is post nerf one of the easiest bosses in the dungeon and is mostly hard if you are attempting achievements.
Double Lash: Cleave attack from behind.
Flaming Breath: Forward cone shaped fire damage breath.
Fireball: Shoots a fireball at a targeted zone.
Because of Scarn’s tail-whip and cone shaped breath Scarn should be tanked perpendicular to the party. All party members should also know to never be on the dragons tail or in front of him to avoid cleave damage.
The party should spread out around the room evenly. While on the ground the boss stays a tank and spank. He will throw up a pulsing fire damage aura that will stack.
In the air phase Scarn will shoot fireballs at the ground and set that ground on fire. You can avoid them very easily and can tell where he is going to hit by the direction he turns his head. This will allow you to take no damage at all.
After he lands he will become a spank and tank again.
Rinse and repeat this until his health hits 0%