What if I told you that there exists an ultra-secret fundamentalist organization filled with highly trained assassins who genuinely believe that they are the saviors of humanity? This doesn't exist in the real world, of course, but it certainly does in Batman's universe of shadows and ruthless villains. Calling itself the League of Shadows or, alternatively, the League of Assassins, this supposedly benevolent group of individuals is notorious for harboring some of the deadliest villains in the DC universe. While casual consumers of Batman content may not be very familiar with the League's operations, the fans more well versed with Batman lore know that while he despises this clan of skilled villains, he also respects it just as much. Created by Denny O'Neill and Neal Adams and led by Ra's al Ghul, this group makes recurring appearances in a number of DC comics.