A bottle is a quest item used during the Defender of Varrock quest. It can be obtained at the end of the first chamber within the Chaos Temple dungeon.
The bottle can be used with the "Red mist" that appears after an Armoured zombie is killed to create a bottle of mist. To pass the doors in the armoured zombie dungeon the bottle must be filled with a certain amount of the "red mist" obtained from killing the zombies.
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