Dr. Darrk has a major problem: the overall storyline that introduced him also introduced classic femme fatale (and daughter of Ras) Talia Al Ghul. Because of this, Dr. Darrk (who was, at the time, presented as nothing less than the head of the League of Assasins) ended up playing second fiddle to the sexy, exotic Talia, an instantly-classic character who would go on to be an enduring love interest for Bruce Wayne and the eventual mother of Batmans son. Unlike most of the League, Darrk was not a martial arts master, nor was he especially interesting visually. He didnt wear a turban or dress like a Ninja; he was just a cold-blooded villain who specialised in manipulation and imaginative death traps. He dispatched his victims quickly, but with a cold, detached sadism that made him compelling to read and fairly scary at the same time. The dream team of Dennis ONeil and Neal Adams created Dr. Darrk during one of the most fertile and exciting eras in the characters rich history. So many classic villains were introduced at this time, that it was only natural that a few slipped through the cracks. Dr. Darrk was one of those few. However, with only a couple of appearances to his name, Ebeneezer Darrk represents that rare thing in comics: a veritable blank slate upon which you could write almost anything. Although Talia killed Darrk (he was shot in the chest and then crushed under an oncoming train, if memory serves), the master-villain could easily have survived. Heck, another villain on this list was once impaled on a weather vane for days and survived by eating rats (so let's not debate realism when discussing a story about a Billionaire who dresses up like a bat in order to fight crime, please). My theory would be that Darrk had made an enemy of Ras Al Ghul, an action for which there is only one recourse, so he faked his death and went underground, biding his time and building a secret army right under his former employers nose. This new army, known as The League of Shadows (to borrow a familiar name from the Nolan-verse) could then take on The League of Assassins at their own game. A team-up with fellow death-trap expert El Sombrero and some of Grant Morrisons Club of Villains characters would be pure gold, in my humble estimation. Darrks most recent appearance was in a flashback during Morrisons Batman Incorporated run. In one very memorable panel, artist Chris Burnham lovingly rendered Darrk as something resembling a Tex Avery caricature of a pervert.