The reduced cadava potion is a potion made by the Apothecary during the quest Making Friends with My Arm by giving him a cadava berry. It is to be given to the Wise Old Man so he can pretend to be dead for My Arm.
If the player attempts to drink the potion, a chat box will appear with the message "However bad the day's been, drinking this is unlikely to make it better."
Once the Wise Old Man drinks the potion, he collapses and the player puts him in a coffin to prove My Arm "killed" the Wise Old Man.
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