Zon-Kuthon - Minor Boon

The Midnight Lord turns your blood and pain into chains of midnight darkness to destroy your foes.

Once, for 1 minute, whenever you take slashing, piercing, or bleed damage, chains rip forth from your body, affecting creatures in a line from your position in the direction of the attack (or in the direction of your choice for bleed damage or if you deal the damage yourself) with the effect of a Grim Tendrils spell whose level is equal to half your level rounded up, and whose DC is your highest spell DC (or 10 + your level + your Wisdom modifier if you have no spell DC).