The raw nerve attacks Yarth again. Meanwhile, the Final Herald casts a spell on herself, making her blurry and indistinct.
Concealed: While concealed, you can still be observed, but you're tougher to target. A creature that you're concealed from must succeed at a DC 5 flat check when targeting you with an attack, spell, or other effect. If the check fails, you aren't affected. Area effects aren't subject to this flat check.
Rolls
Nerve Ending vs Yarth - (d20+20, d20+16, d20+12)
d20+20 : (15) + 20 = 35
d20+16 : (9) + 16 = 25
d20+12 : (18) + 12 = 30
Damage - (2d10+9)
(92) + 9 = 20