A part of the Hymns talent tree.
Hymn of Perseverance: sustained, 20 negative, 12 cooldown, instant cast +(15 + 7.1 * talent) % stun, confusion, and blinding resistance, and +(0.23 * [10 + spellpower] * talent modifier) rescaled darkness damage when hit in melee.
Gives you resistances to mental effects, and deals darkness damage to those who attack you.