Batman boasts some of the most iconic villains in comic book history, including the nihilistic Joker and the power-obsessed Ra's al Ghul, but there is only one villain who shares a deeply personal connection with the Caped Crusader: Hush. One of Batman's greatest, and most underrated foes, Hush earned the hero's begrudging respect in a way few other enemies, if any, ever have.
https://screenrant.com/batman-villains-joker-ras-al-ghul-hush-beyond/