Breath of the Black

Close-quarters spell
One nearby enemy; breath weapon
Charisma + Level vs. MD
10d6 + Charisma acid damage, and 20 ongoing acid damage.
10 ongoing acid damage.
7th Level Spell: 
10d10 damage, and 40 ongoing damage; 20 ongoing on a miss.
9th Level Spell: 
2d6 x 10 damage, and 60 ongoing damage; 30 ongoing on a miss.
Epic Feat: 

Double the spell's ongoing damage on a miss.

Breath Weapon: 

For the rest of the battle, roll a d20 at the start of each of your turns; on a 16+, you can use breath of the black that turn if you wish.