To create the Acid Maul, combine a Maul with any item in the "chemical" category. The blueprints for the acid maul are found in the Medieval Town Museum in Medieval Town.
It is a heavy weapon that causes acid splash damage if swung into a group of zombies. There is also a golden version of this combo weapon which can be created using a gold bar and an Acid Maul.
Killing 30 Fresh Zombies with the Acid Maul is required for completion of the Hammer Time combat trial.
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