Neptune's Shell

Type	AccessoryCrafting material
Tooltip	Transforms the holder into merfolk when entering water
Rarity
Sell	7 GC50 SC
Research	1 required
Buff	Merfolk
Buff tooltip	Can breathe and move easily underwater
Duration	While underwater

Merfolk form

Neptune's Shell is a Hardmode accessory that aids maneuverability in water, honey, and shimmer(Desktop, Console and Mobile versions) by granting indefinite breathing time while submerged, swimming via the ↷ Jump key, and eliminating the slow movement speed usually caused by submerging underwater. Entering applicable liquids with this accessory equipped transforms the player into a merperson and grants the Merfolk buff. While in this form, the breath meter will refill as if the player is in open air, therefore effectively preventing drowning.

Neptune's Shell has a 1/50 (2%) / 99/2500 (3.96%) chance of being dropped by Creatures from the Deep.

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

Crafting

Used in

Result	Ingredients	Crafting station
Moon Shell	Moon Charm Neptune's Shell	Tinkerer's Workshop

Notes

Swimming functions similarly to that of a Flipper or Flipper Potion, and its speed nears that of flying through the air with wings.
Swimming in honey activates all the perks of the Merfolk form but does not allow the player to move at full speed.
Landing in and "jumping" from water alone (by swimming up past the surface), without touching land, does not reset flight time for wings or variants of Rocket Boots.
The Merfolk form is affected by dyes, these are applied via the player's armor slots rather than the one attributed to the accessory slot that the shell is equipped in.
The Merfolk effect takes priority over the benefits of the Moon Charm and its upgrades, causing the player to lose the Werewolf's bonuses while in water.
Neptune's Shell can also be equipped as a vanity accessory, which causes the Merfolk form to appear regardless of whether the player is in water. This is merely the appearance of the Merfolk, the buff will not take effect while it is equipped as a vanity (caution should be taken when in water, as the player will need to watch their breath meter).
(Desktop, Console and Mobile versions) Wearing a Fish Bowl or having the Gills buff in For the worthy(Desktop, Console and Mobile versions) will activate the Merfolk appearance and infinite breathing time, but not the Merfolk buff.

Tips

An easier/faster way to get Neptune's Shell is by placing a Water Candle and/or consuming the Battle Potion because the Solar Eclipse does not have a set spawn rate.