Call on Ilmater

You reach up your LEFT hand to the sky and call upon the mighty god of endurance. Who bestows upon you, the divine blessing of controlled retribution. (basically a controlled living nightmare)

Mindless Rage: while under the divine blessing, Surtr is immune to being charmed and frightened. If he is already charmed or frightened and enters the rage, the effect is suspended for the duration. You gain an additional 1d6 damage while the spell is active.

Surtr is unable to focus on spellcasting during the duration. no spells can be cast during the spell.