The Nidbathed of Nidavangr have extra souls on them, giving them an unusual sort of extra lives. If they would die, even through a soul-slaying, one of their scars will disappear and negate the hit. This is sorta like a cross between Luck and Twist Fate.

A Scar Soul always works. It is not yet clear if these are used before traditional extra lives. Scar Souls do not get their bearers out of "sticky situations", such as being swallowed or being stuck in another Plane. Scar Souls only prevent death in single bursts, meaning the bearer will die if they end up Underwater without Water Breathing.

Getting Scar Souls is a one-time process that happens when one is recruited. They are gone for good if spent. You can control how many Scar Souls a new Nidbathed or Nidhere gets through the strength of Nidavangr's Dominion in Nidavangr's capital. The starting Scar Soul count of a Nidhere always matches the province's Dominion at the time, while that of a Nidbathed is generally half as many.

What even ARE Scar Souls? Well, a Nidbathed (or Nidhere) enters the Nidakettil with his friends, gets beaten and cut within an inch of their life by said friends, and watches them all commit suicide out of guilt. The Scar Souls are the souls of his friends, or at least those who managed to bond with the scars they inflicted.