This last PTR build contains reference to the upcoming Season 3 affix, named Encrypted! Here's what datamining says about this affix:
NEW Encrypted Enemies throughout the dungeon summon Automa when engaged in combat. Defeat the Automa to unlock the First Ones' secrets and gain powerful bonuses.Currently it's not much but we're sure to see more in upcoming PTR builds. Based on the description, this will likely increase pack size throughout the dungeon. Could this be a more AoE focused affix
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