Wine of Zemouregal is used with a doogle potion (unf) to make Zemouregal brew and complete the "Micro Brew" achievement in the hard set of the New Varrock Tasks. It can be found by using a jug on the barrels in the store room in the south-west corner of the New Varrock palace.
Drinking it heals 875 life points and causes your Attack level to go down by 2. You can continuously refill from the barrels to safely restore all missing life points if you don't mind the attack penalty.
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