<P> Batman: Birth of the Demon provides a rough figure of 500 years for Ra's al Ghul's age . Due to living so long, he is assumed to have lost track of how old he is . Azrael #6 (July 1995; written by Dennis O'Neil) places Ra's age closer to 450 years . As he tells Jean Paul Valley, "I appear to be a vigorous fifty . I am actually a very vigorous four hundred and forty - eight...or is it four hundred and fifty - three? I lost count during the Black Plague . No matter". In Batman Annual #25 (published in 2006), Ra's al Ghul is described as a "700 - Year Old International Terrorist". </P> <P> Using the Lazarus Pits to extend his life, Ra's spends the next several centuries journeying the world . He fights in the French Revolution and the Napoleonic Wars and becomes a formidable warrior . As the world entered the modern age and industrialization began to cover much of the Earth, Ra's grew to despise the humans who he believed were destroying the world's natural beauty, thus setting him on a path of eco-terrorism . Also during this time, Ra's, his uncle, and the boy who freed him from the sultan are all using the Lazarus Pits to prolong their lives until an incident in London . Ra's catches the boy writing his own memoirs in their original language, of which Ra's has forbidden all records . During a battle, Ra's kills the boy and flees to a Lazarus Pit, which he uses . When he returns to their home in London, his uncle has vanished with the remnants of their historical records . </P> <P> Over time, he becomes a master of many forms of combat, notably fencing . He also builds up vast wealth and creates The Demon, a huge international organization . According to Justice League of America (1st series) #94; "It has been whispered in the darkest places for 500 years that a cartel of criminals has slowly sucked its way into the rich veins of the Earth . Many are its names spit from the mouths of men, but most often it is cursed only as . The Demon . It has a leader . A Head". The League of Assassins, one of the many smaller organizations making up The Demon, is thus sometimes called "The Demon's Fang" or "Demonfang". </P> <P> Ra's returns to prominence and comes dangerously close to realizing his dream of worldwide genocide in the "Contagion" story arc of the Batman titles . His organization unleashes a deadly virus known as Ebola Gulf A (a.k.a. "The Clench") in Gotham City, putting Batman in conflict with a force he seemingly cannot defeat . A cure is eventually located by Batman and his allies, though the mastermind behind the outbreak is not discovered until the follow - up story "Legacy". </P>

Who killed ra's al ghul in dc comics