Amulet of the Tides

Amulet of the Tides:

Wondrous Item (Amulet), Rare (requires attunement)
This amulet is made of a shimmering blue crystal, resembling a droplet of water suspended in mid-air.
Abilities: While wearing this amulet, you have advantage on saving throws against being charmed or frightened. Additionally, once per long rest, you can use an action to cast the Water Breathing spell on yourself without expending a spell slot.

Notes: Deception, Jewelry