• Torment Difficulty:
Unique items can drop in Torment difficulty, with higher difficulties increasing your odds.
• Boss Hoards:
From patch notes Temerity is listed from as dropping from several boss hoards, including Varshan, Lord Zir, Grigoire, Echo of Duriel, The Beast in the Ice, and Urivar.
• Open World Drops:
Temerity can randomly drop from enemies, chests, and breakable objects.
• Helltide Chests: Temerity can drop from chests during Helltide Events.
• Boss Farming:
Repeated boss hoard runs are the best farming method if you specifically want Temerity.