Vault of the Watery Warden

Hidden beneath a collapsed quay, a small semicircular cistern served as the lair and lock for a watery treasury. The water weird, bound to the basin's carved runes, animated to repel intruders and kept the chest's contents suspended and chilled. When the creature was driven off or stilled, the party found a watertight oaken coffer sealed with barnacled iron and a scattering of items caught among reeds and carved alcoves — pieces of a modest but oddly curated magical hoard suited to travelers who ply seas and rivers. Everything smells faintly of brine and salt; some pieces carry the residue of old enchantments meant to soothe or control water.