Coldfire Flask

Wondrous item, uncommon

This crystal flask is filled with a bubbling blue liquid. It's warm to the touch near the top of the bottle, but cool toward the bottom. When found, the flask has 1d6 + 4 uses of liquid inside.

You can use an action to pour any number of remaining uses from the bottle into an unoccupied space on the ground within 5 feet of you. When you do, the liquid creates a Small blue flame, like a campfire, which doesn't use oxygen; it can be covered or hidden but not smothered or quenched. The flame burns for a number of hours equal to eight times the number of uses poured from the flask. The flame doesn't grow or spread from where the liquid was poured.

When you pour the flask, you can choose whether the flame is hot or cold. A hot flame staves off cold like a normal fire, but a cold flame staves of extreme heat in the same way. A creature within 10 feet of the flame can feel the effects of its heat or cold.

A creature that enters the flame for the first time on a turn or starts its turn there must succeed on a DC 13 Dexterity saving throw if it's a hot flame or a DC 13 Constitution saving throw if it's a cold one. On a failed save, the creature takes 1d8 fire or cold damage, respectively.

'Twas a strange sight, us gathered at the cookfire under the sweltering desert sun. Stranger still when seen closer: instead of simmering stew our pot held iced desserts rimed with condensation above a sapphire flame, frosty mugs of ale pressed into the sand all around. Veterans of desert treks all, not one of us could remember a day of such comfort, wonder, or revelry in such searing climes.