Hmm. +2 to "destructive" spells, take fallout with no Power reduction with Sponsor Debt. Sounds like a [-5] magic to me. I'll make the adjustments.
HELLFIRE V.2.1 [-5]
Description: You are a wielder of Hellfire, the power of Hell and the fire of Destruction.
Sponsor: Hell. Can also be granted by demons or demon lords, or even Lucifer himself.
Agenda: The sinister agenda of Hell. May correspond to the agenda of a specific demon if granted by a specific demon. Destroy things. Be wrathful, prideful, vengeful, greedy, envious, lustful, slothful, or gluttony.
Evocation: Hellfire typically involves a brimstone-reeking angry crimson flame, but can also include elements of raw destruction, smoke, darkness, death, corruption, sin, and unholiness
Thaumaturgy: Hellfire grants it’s users the ability to use demonic energies in their rituals, curse their foes, and strike them down from afar, granting Diabolism, Entropomancy, and Disruption.
Evothaum: Normally, any ritual that can be cast with Hellfire can be cast with Evocation’s speed and methods, but the sponsor (be it Hell itself, Lucifer, or a demon lord) might demand a point of sponsor debt on specific occasions.
Extra Benefits: Hellfire is a force of destruction, and when employed in such spells, it’s power is awful to behold. Any spell involving destruction or sin cast with Hellfire gains 2 extra shifts: an attack’s Weapon rating would rise by +2, an evothaumic Might roll to break a wall would gain a +2 bonus, and a psychomantic block blasting the target with greed would gain a +2 bonus. In addition, spells enhanced by Hellfire retain their devastating power no matter how poorly controlled: When casting a spell with Hellfire, you can take take a point of Sponsor Debt in order to take shifts of fallout without reducing the actual power of the spell.