Pearl Abyss announced today that the new system "Mastery" has been updated in&nbsp;<i>Shadow Arena.&nbsp;</i>&nbsp;&nbsp;. Mastery is a system that allows players to additionally select another skill for their Hero based on their preferred concepts. By adding an offensive Mastery skill to a support type Hero, they become aggressive with their defensive skills strengthened. Players cannot know the opponents' Mastery skills until the battle starts, making each battle more tense and strategic.&nbsp