Ra's al Ghul (Arabic for "The Demon's Head," also known by the alias of Henri Ducard) is the immortal head of the League of Shadows and the main antagonist of the first part of the Gotham City campaign in Return of the Keyblade. One of the oldest living alumni of HYDRA, keeping himself alive over the years using the youth-replenishing Lazarus Pit, Ra's grew disenchanted with HYDRA's philosophy of bringing order to the universe and formed his own splinter group to protect life from the corruption of HYDRA and its shadowy masters at any cost, eliminating those who the League believes are falling to the Dark Side. Though he trained a young Bruce Wayne in the ways of the League, Wayne refused to follow Ra's' extreme philosophy, making the Batman an obstacle in Ra's' goal of destroying a corrupt Gotham.
"Crime. Despair. This was not how man was supposed to live. The League of Shadows has been a check against human corruption for thousands of years. We sacked Rome, loaded trade ships with plague rats. Burned London to the ground. Every time a civilization reaches the pinnacle of its decadence, we return to restore the balance."
Ra's al Ghul was born in what is now the Levant in the 300s BC. He was a member of a minor tribe that lived in peace for many years until the Greek conquerer Alexander the Great passed through on the way to Egypt. Although al Ghul's tribe was guilty of nothing more than simply being in Alexander's way, the Greeks massacred almost the entire tribe, leaving only al Ghul and a few survivors. The group was approached by Alveus Hive and his Inhuman cult, the beginnings of what would one day become HYDRA, offering to help them take vengeance upon Alexander in return for their loyalty. Al Ghul and his brethren agreed and, with Hive's help, poisoned Alexander in Babylon after his return from India in 323 BC.
Al Ghul and his men helped Hive expand his cult's influence throughout the universe, all the while believing they were a force for good helping to punish the corrupt and uplifting the powerless. That all changed when Hive invited al Ghul to join him in America for a secret ritual. On what would become Arkham Island in the present-day Gotham City, Hive attempted to summon his dark master, the Dweller-in-Darkness. Seeing for the first time Hive's true intentions, al Ghul decided he would have no further part in the subjugation of the universe under the Old Ones' name. Turning against Hive, al Ghul interrupted the ritual and prevented the Dweller-in-Darkness complete summoning, though the Dweller's evil would corrupt the surrounding area for centuries afterward. For his treachery, Hive slew al Ghul.
Al Ghul's former tribesmen and other cult members who disagreed with Hive's goals took al Ghul's body back to the Middle East, where they immersed him in the legendary Lazarus Pit, a pool of unknown origins whose waters could restore the dead to life. Brought back, al Ghul swore eternal enmity to Hive and his followers, organizing his loyalists into a new organization which would protect the universe from Hive's cult and its shadowy masters. The League of Shadows had been born.
Through the years to come, the League waged a long and bloody war against HYDRA and its pawns. Al Ghul claims that the League was responsible for the sacking of Rome, the spread of the Black Plague, and the Great Fire of London, all in an effort to deny HYDRA a foothold. Many casualties were claimed on both sides, as well as unfortunate innocents caught in the crossfire, but eventually, HYDRA was driven from al Ghul's homeworld of Earth-Prime.
Seeking to punish al Ghul for his resistance and reestablish their presence on Earth-Prime, HYDRA has long looked for allies to use against the League's founder. In the aftermath of World War II, they found one in the Japanese ninja master known only as the Sensei. The Sensei had also used a Lazarus Pit's properties to extend his own lifespan, and thus attracted al Ghul's notice. The energies of a Lazarus Pit weakened with each use, forcing al Ghul to seek out new ones once one was fully depleted. Al Ghul forged an alliance with the Sensei in order to share the Lazarus Pit in Japan, though the Sensei secretly desired sole ownership of it. To cement their alliance, al Ghul married the Sensei's daughter and fathered twin girls with her, Talia and Nyssa. The Sensei also instructed al Ghul and the League in the ways of ninjustu.
HYDRA approached the Sensei and offered to allow him to reclaim his Lazarus Pit in exchange for leading a rebellion against the League. The Sensei agreed and led a coup against al Ghul, imprisoning his own daughter and granddaughter Talia in the prison of Pena Duro in Central America to keep them from interfering (Nyssa had left on her own due to disagreements with her father's hardline methods). Though al Ghul managed to defeat the Sensei and force him into hiding, he was too late to save his wife from being murdered by the Pena Duro inmates. Talia was protected by the man who would come to be known as Bane, for which al Ghul rewarded him with membership in the League.
Knowing that his Lazarus Pit supply is running out, al Ghul has recently begun looking for a successor to take up his crusade against HYDRA. Seeing a kindred spirit in a young Bruce Wayne, whose parents had been murdered in Gotham City (secretly as an indirect result of a financial crisis caused by the League in an attempt to purge the city of the Dweller-in-Darkness' remaining evil), al Ghul took him in and personally trained him in the ways of the League. However, Wayne refused to kill in the League's name and rebelled against them when he discovered the League's intentions for Gotham. Despite this, al Ghul still holds out hope that Wayne can eventually be convinced of the righteousness of the League's cause.
Return of the Keyblade
(fulfills his role from Batman Begins, with further appearances planned down the line fulfilling his roles in The Dark Knight Rises and Batman: Arkham City.)