Vertigo Comics is an imprint of DC Comics, created in 1993 to house the company's mature readers comics, including Hellblazer and Swamp Thing. It also publishes a number of creator-owned comic book series, including such notable titles as Fables, Y: The Last Man and 100 Bullets.
In 2011, with superhero comics having become increasingly violent and aimed at mature readers, this rule was relaxed, allowing a DC version of John Constantine to exist in the DC Universe, while the original continued to star in Hellblazer until its cancellation in 2013.