Shark Tooth Crown
Wondrous item, rare (requires attunement)
Shark’s teeth of varying sizes adorn this simple leather headband. The teeth pile one atop the other in a jumble of sharp points and flat sides. Three particularly large teeth are stained with crimson dye. The teeth move slightly of their own accord when you are within 1 mile of a large body of saltwater. The effect is one of snapping and clacking, producing a sound not unlike a crab’s claw. While wearing this headband, you have advantage on Wisdom (Survival) checks to find your way when in a large body of saltwater or pilot a vessel on a large body of saltwater.
In addition, you can use a bonus action to cast the command spell (save DC 15) from the crown. If the target is a beast with an Intelligence of 3 or lower that can breathe water, it automatically fails the saving throw. The headband can’t be used this way again until the next dawn.