The Brine Covenant appears as crystalline salt patterns forming across the bearer's shoulders and arms, creating intricate geometric designs that shimmer with a faint blue-white glow. The mark serves as permanent proof of survival against the brine storms - competitors bearing this mark become immune to the corrosive effects of future storms. The pattern cannot be removed and only fades when the bearer is finally culled, making it both badge and warning.

The Brine Covenant serves as a protective network across all leagues - bearers recognize each other through their salt-crusted skin and tend to watch out for fellow survivors. This creates a series-spanning faction that challenges the individualistic survival doctrine by demonstrating that those who adapt to the frontier's corruption rather than fighting it are equally worthy of remembrance.