Volcanic Storm

Evocation [fire]
Level: Artificer * 4, Bloodrager * 4, Druid * 4, Hunter * 4, Sorcerer */Wizard * 4, Warlock * 4
Components: V, S, M/DF (obsidian and ash)
Casting Time: 1 Standard Action
Range: long (400 ft. + 40 ft./level)
Area: cylinder (20-ft. radius, 40 ft. high)
Duration: 1 round/level (D)
Saving Throw: None
Spell Resistance: yes
  Chunks of hot volcanic rock and clumps of ash pound down when this spell is cast, dealing 3d6 points of bludgeoning damage and 2d6 points of fire damage to every creature in the area. This damage only occurs once, when the spell is cast.
  For the remaining duration of the spell, heavy ash rains down in the area. Creatures inside this area take a -4 penalty on Perception skill checks and the entire area is treated as Difficult Terrain. At the end of the duration, the rock and ash disappear, leaving no aftereffects (other than the damage dealt).