Molly is a miniature version of the Giant Mole that can be unlocked as a pet from a Rotten fang, which is obtained as a drop from killing the Giant Mole. The chances of obtaining the item is 1/2,500 for normal mode, with a threshold of 500, and 1/500 for hard mode (explanation of drop mechanics). After the item is used, Molly can be summoned from the pets tab in the hero interface.
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