The hottest pop star in Europa, who just happens to also be a mutant with enhanced powers of empathy (meaning, we guess, that she really, really, really knows your pain, man). She is electrocuted by a microphone, then returns from the dead, leaves her fictional country, and becomes a crime-fighter as a member of X-Statix. Then she dies again, and her posthumously released single (aptly titled "Back From the Dead") kills anyone who sang it, a reference to the 1985 Mr. Mister single "Kyrie," which has the same effect. (Seriously, it does! Try it yourself!1) Hunter's appearances came in issues 13-18 of quirky Marvel mutant comic X-Statix (October 2003-March 2004).
1The Rocklopedia Fakebandica is not responsible for negative effects resulting from this suggestion, including death or remembering the lyrics to "Kyrie."
Hunter was originally supposed to be a returned-to-life Princess Diana, but Marvel higher-ups squashed the idea.