Origin
One of the principal gods of the Aztecs, ruling over the lesser gods of the underworld. He and his wife also served as the guardians of the bones of all those who died including, the previous generation of gods. several gods however manged to take some of these bones back to the living plain where they would be used to create the mortal races.
For anyone who died they would give gifts to Mictlantecuhtli and his wife, to gain favor and ask for requests, including returning to life.
The worship of Mictlantecuhtli would include a portion where cannibalism was required, as a way to speed up the decomposition of another person, and bring them closer to the lower levels of the underworld.
Vertigo Comics
Mitctlantecuhtli appears as one of the prime villains for John Constantine,as he believes he is stepping into his business.
Lord Fanny has several meeting with the death god, in which he helps her by giving her powers, and showing her how to defeat several super natural enemies.
Powers
Being a god he is omniscient, he can control the dead and bring people back to life and kill them nearly at will.