Aptly named, Threnody (Deathsong) is intune with the death energies of the whole human populace. She literally feels people dying and is capable of absorbing energy from death making her stronger, faster and capable of releasing blasts of energy. Due to the unique nature of the Legacy Virus, Threnody's powers began going wild when mutants were pushed over the edge into death in a final display of their mutnat powers. Living on the streets, Threnody was found by the X-Men, Rogue, Beast, and Iceman while they were investigating a doctor's clinic researching into the Virus. The trio, however, didn't find her alone. They confronted Mr. Sinister who wanted to take Threnody into his care. Though they argued over it, the X-Men had to consent that Mr. Sinister would be the only one would could help her properly control her powers and put her to the most use with his scientific dedication to curing the Legacy Virus.

   When next the X-Men found her, deep within Mr. Sinister's lair, she was considerably more lucid and able to fully control her powers due to six metal attatchments to her head. Helping the X-Men to destroy Sinister's huge database of knowledge, she remained in Sinister's clutches as an undercover agent of sorts. With such incredible information at her disposal, Threnody soon discovered the AoA refugee known as X-Man and began planning her escape from Sinister. Keeping knowledge of him from Sinister, she planned on using him as her human shield. Running through the sewers beneath Paris with the Marauders on her tail. Luckily X-Man found her and killed the hunters. Staying close by her side, the two settled in New York, living together and developing more than a friendship.

   After a time, Threnody began feeding off the poor and terminally ill in order to become stronger and stronger. The vampiric creature known as Morbius made her aquantiance seeing her a fellow creature of death. Threnody felt she only deserved to live as one with Morbius and fought Spiderman and X-Man when they confronted the pair. Nate gave Threnody an ultimatium: Come back and work through the problems, or leave. Before she could return to their apartment, however, Madelyne Pryor found her in her search for Nate. Refusing to tell her anything and attempting to scare her with Sinister's name, the two became peaceful combattants of sorts. When Threnody told Madelyne she was still dead, it enraged Madelyne into killing Threnody. Thinking her to have abandoned him, X-Man came back to the scene of their last encounter and couldn't 'hear' Threnody wih his mind, thus confirming his suspicions.

   When Nate seemingly died, the specter of Threnody came to him telling him to live and that she had returned for him. Seemingly using her death manipulating powers, Threnody cheated death and came back. Spotted in the Lair of the Lost, she appears to be feeding on those she finds beneath New York.