Only Leo, Percy, Frank and Jason remain from the seven. Thalia is still with the hunt and Nico lives at camp. After the war... After the deaths, Percy joined S.H.I.E.L.D. Lots more - detailed background to beginning of book is in Prologue. Disclaimer for whole book - I don't own any characters in this book, they are the property of the geniuses Rick Riordan and Marvel.