HX-N1 is a synthetically engineered influenza virus designed as a form of mutagenic biological warfare. Designed by the Sublime Corporation's CEO, Lobe, it was tailor-made to affect at least one-hundred thirty-four known mutants across the globe. This super-strain possessed a power-dampening effect that robbed a mutant of their extranormal abilities, and caused severe complications for those with a complete mutant physiology.
The virus came about as part of a defense mechanism in Lobe's ongoing efforts to replicate mutant powers. During a fight with Fantomex and the X-Men, he released the HX-N1 into the atmosphere and used it to cover his escape. Fantomex managed to acquire a sample of the virus and ran it through the computer systems aboard his personal carrier E.V.A.. Afterward, he gave the samples to the X-Men for further study.
When the X-Men attacked Lobe, he activated the "Ebola Plus" function to defeat them, but him and his investors for the mutant powers drug, who were mutants for the time of the drug Xperience's effects. Lobe purge everybody from the HX-N1.