Armor of Avernus (5e Spell)
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|V, S, M (A vial of blood)
You touch a willing creature, and a protective layer of force surrounds them. Their armor class increases by 2 for the duration, and any creature that hits them with a melee attack takes fire damage equal to 2d4 + your spellcasting ability modifier. You may dismiss this spell as an action.
At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d4 for each slot level above 3rd. If you cast the spell using a spell slot of 5th level or higher, the armor class bonus increases to +3. If you cast the spell using a spell slot of 8th level or higher, the armor class bonus increases to +4.