Threnody is a supervillain appearing in American comic books published by Marvel Comics. Created by Fabian Nicieza and Richard Bennett, Threnody first appeared in X-Men (vol. 2) #27 (October 1993), but was previously shown in Stryfe's Strike File #1 (November 1992). Melody Jacobs is a mutant with the ability to sense and absorb death energy. She is sustained by these energies and becomes addicted to them.

She was an ally to X-Man, but later became a supervillain due to her need for death energies.

Melody Jacobs was born in Manhattan and led a normal life until her mutant powers manifested in adolescence. She found herself feeding off of the energies released by the dead and the dying, with residual slivers of the dead's souls lingering and damaging her psyche. Melody became a runaway, before being found by Abomination (Emil Blonsky), who had established himself as the lord of a clan of homeless and runaways known as the Forgotten, who took refuge in the sewers under the city. Melody spent weeks lying in a fugue-like state in Blonsky's lair, cared for by the Forgotten. She was named "Threnody" after the mournful cries she made in between her brief periods of lucidity.

Over time, Threnody builds up power which is violently released as a "death-purge", killing her caretakers. Threnody flees and lives on the streets of Los Angeles. She later meets Gordon Lefferts, a geneticist in the employ of Mister Sinister and the first mutant exposed to the Legacy Virus. Lefferts identifies the virus within him and begins studying it for a possible cause and cure, while Threnody and other homeless take residence in his lab. Sinister sees that Threnody has potential to track infected mutants and takes her under his care with Beast's permission.

Threnody quickly improves under the care of Mister Sinister, who designs small neuro-locks that prevent her stored energy from being releasing unintentionally. Threnody in turn is used as a tracking system with Legacy Virus-afflicted mutants while working as Sinister's assistant. Threnody escapes to Paris, but is pursued by Sinister's Marauders. She is rescued by Nate Grey (X-Man). Nate accidentally disrupts Threnody's neuro-locks, causing a massive explosion that he contains with his telekinesis.

Threnody travels to Greece with Nate, where they battle the villain Holocaust. During the battle, Threnody discovers that she is able to absorb the energy of the dying, killing them in a non-violent manner. Once she and Nate return to New York, Threnody separates from him without explaining her motivations. She is once again pursued by the Marauders, but is saved by Abomination. He blames her for the deaths of the Forgotten years prior. Nate experiences Abomination's memories of the incident, but forgives Threnody for her actions. The two leave the tunnels and Threnody finally puts her past with the Forgotten behind.

Threnody and Nate begin living together in a SoHo loft. Nate develops a following as a street psychic in Washington Square Park, earning them some spending money. However, Threnody's powers evolve to the extent that she no longer requires normal sustenance, surviving only on the death energy she absorbs. Eventually, Nate pushes her away and she returns to the streets. Threnody is attacked by Madelyne Pryor, who sucks her of her energy.

Threnody is left for dead in St. Raymond's Cemetery and taken to a morgue. She consumes the death energy inside the morgue, restoring her to life. Threnody's powers evolve further, causing her to resurrect nearby corpses as zombie-like beings. Seeking to feed, Threnody stumbles into the Last Lair after the psychotic Jackknife massacred the entire gang and feeds on the lingering death energy. She remains in the Morlock tunnels until she discovers Dark Beast's labs nearby. Threnody chooses to relocate before Dark Beast can find her.