Bottled Water (5e Equipment)
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Wondrous Item, rare
Found floating in the ocean from an unknown source, these little tin canisters hold small water elementals. When the cork is removed from the bottle the trapped elemental escapes with a forceful burst.
The bottle can be fixed to an arrow, bolt, dart or javelin. When the ammunition or weapon is used to make a ranged attack, it puts out an area of fire within a 15-foot cube, and if it hits the target takes an additional 1d6 cold damage.
Alternatively, the bottle can be held in one hand and used when you use your Attack action to extinguish an 15-foot cube of fire, or douse and push a creature 15 feet away. If you do so you have advantage on your Strength (Athletics) check.
Once a bottle has been used, the elemental disperses and the canister becomes a small nonmagical container.