WARNING: The following contains spoilers for Locke & Key/The Sandman Universe: Hell & Gone #2, on sale now from DC Comics and IDW Publishing.

While the events of The Sandman were usually pretty far removed from the events of the DC Universe, Morpheus and the Endless' adventures ostensibly took place in the same world as Superman, Batman and the like. John Constantine teamed up with Morpheus in an early tale, and the old Justice League supervillain Doctor Destiny memorably menacing the Lord of Dreams in a terrifying showdown.

And as The Sandman Universe continues its crossover with Locke & Key, one fan-favorite Justice League Dark member gets their familiar personality trait when Etrigan the Demon joins up with Mary Locke for her journey into the depths of Hell.

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Sandman Etrigan

Mary's brother Jack Locke, the heir to Keyhouse the mystical primary location of Locke & Key, was relegated to Hell after all the carnage he participated in during World War I. Years later, Mary searched for a way to free Jack's soul from Hell, eventually leading her to the Dreaming and gain possession of a key to Hell. However, with Morpheus imprisoned by a sinister cult, led by Roderick Burgess, seeking to ensnare Morpheus' sister Death and Mary encountering the murderous Corinthian, she decides to summon a different figure to guide her through Hell to reunite with her brother. Using a rare text from Morpheus' personal library, Mary summons Etrigan through an occult ceremony in Locke & Key/The Sandman Universe: Hell & Gone #2 by Joe Hill, Gabriel Rodriguez, Jay Fotos and Shawn Lee, where Etrigan reveals he has not yet earned the right to become a full-fledged rhyming demon.

As Mary summons Etrigan with a variation of his namesake rhyme, the Demon reveals that only the higher ranks demons in Hell hold the title of rhyming demons. Despite his lowly rank, Etrigan agrees to guide Mary through Hell to find Jack, eventually leading to a confrontation with Lucifer Morningstar himself. While Lucifer plots to keep Mary in Hell with her brother Jack, she reveals that she also entered into the netherworld with Morpheus' righthand man Fiddler's Green, a mystical being who can also teleport others with him through space and time. Taking advantage of this ability, the Locke siblings and Fiddler's Green make their escape while the entire escapade results in Etrigan receiving a promotion which he gleefully embraces as all of his dialogue takes on the familiar rhyming structure.

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Etrigan Locke and Key Sandman

Etrigan's appearance on the Locke & Key/Sandman crossover is a nod to the demon's early appearance in the main Sandman comic book series. Appearing in 1989's The Sandman #4 by Neil Gaiman, Sam Kieth, Mike Dringenberg, Robbie Busch and Todd Klein, Etrigan greeted Morpheus when he entered Hell to recover his helm, which was stolen from him while he was imprisoned by a cult for decades. Guiding Morpheus to be granted an audience with Lucifer, Etrigan retains the rank of rhyming demon, one that he has appeared as in many of the DC adventures.

Mary's adventure through Hell provides a nice parallel to Morpheus' own journey to recover his helm from Lucifer decades later, albeit with Mary going into the netherworld more prepared than the Lord of Dreams. With an audibly lower ranked Etrigan and Fiddler's Green, Mary was able to locate her brother and escape from an enraged Lucifer. And though Mary may not have the happiest ending as she and Jack make it out of Hell, she outsmarted the Devil himself while helping Etrigan finally get that hellish promotion he long craved.

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