Neptune's Shell

Neptune's Shell is a Hardmode accessory that aids underwater performance by granting indefinite breathing time underwater and swimming via the key, as well as eliminating the slow movement speed usually caused by water. On the, it has a 2% / (1/50 / ) chance to drop from Creature from the Deep during a Solar Eclipse event. On the s and s, it is only obtained through crafting.

Entering water with this accessory equipped transforms the player into Merfolk, a buff with no time limit. While in this form, water's usual effects are negated. The breath meter will not decrease, therefore effectively preventing drowning, and movement through water is faster than on dry land. Holding the key also makes the character swim (fly continuously upward) in water, while falling faster than you would on land.

Neptune's Shell can be considered an upgrade from the Diving Gear in most respects, but lacks the underwater lighting of the Jellyfish Diving Gear and the extra mobility on ice of the Arctic Diving Gear.

Trivia

 * The name of the item refers to the Roman god, Neptune, god of the sea

History
Coquillage de Neptune