Helpfile says:

Syntax: commune/cast 'primordial vengeance'

By pronouncing this curse, the druid or ranger calls upon the spirits of the surrounding nature to follow and punish a single foe. If successful, misfortune will follow the afflicted so long as they stand within unspoiled terrain, taking a myriad of forms as the angered spirits take their revenge.
Those who are most comfortable in the wilds are
the least vulnerable to this, as their harmony with nature keeps the
spirits at bay. Though the curse may be removed, it must be done
among the spirits of nature, where forgiveness can be found.


I wonder what kind of 'punishment' it does? Looks like continous effects (like arc of lightnings) but if you ever had it cast on you, I'd like too have more info about it...

thank you.