The Elemental in a Bottle is a Hardmodeaccessory that has a 14.29% / 20% chance to be dropped by Sand Elementals. Equipping it summons a Sand Elemental to fight for you, which deals summon damage and casts sandstorms in a similar fashion to their enemy counterpart.
The tornadoes summoned do not have a damage type, and are unaffected by summoning damage bonuses.
The Sand Elemental can deal contact damage to enemies 3 times per second as a default, 4 times per second after the Golem is defeated, 6 times per second after the Moon Lord has been defeated, 10 times per second after The Devourer of Gods has been defeated and 20 times per second after Jungle Dragon, Yharon has been defeated.
The sand tornadoes also deal damage at the same increasingly frequent intervals as the game progresses.
Sand tornadoes pierce two enemies before disappearing on the third before defeating the Moon Lord. Afterward, the sand tornadoes gain infinite piercing.
This item used to be called "Waifu in a Bottle", while the Sand Elemental herself used to be called "Sand Waifu". After that, they were known as "Lady in a Bottle" and "Miss Sandy", respectively.