Dana is Daniel X's girlfriend. She appears in all four books. Dana and the rest of Daniel's gang were back on Daniel's home planet, when she and the rest of his friends were killed during FirstStrike.
Dana was killed in the FirstStrike, but in the original 6 books,(The Dangerous Days of Daniel X,Watch the Skies, Demon and Druids, Game Over, Armageddon, and Lights Out) In Armageddon Daniel finds this girl called Melody or Mel. Later on he discovers that Mel is Dana in another form after she died.Status- Alive as Mel on Terra Firma (Earth)