As marketing stunts go, this one has "killed" it. The “death” of a beloved mascot has sparked the kind of online frenzy that advertisers dream of, with everyone from the World Health Organization to ...

Call it a miracle, or a marketing ploy: Duo the owl is back from the dead. Two weeks after announcing the murder of its sassy green mascot, the language-learning platform Duolingo now says he's fine — ...