How did Bruce Wayne die....and is nightwing the only one to become the new batman?

-Darkseid seemed to kill Batman, but really just sent him back in time in a effort to use him as a literal time bomb (someon's idea of a pun?). Who would replace him was an issue, but in the end Dick Grayson assumed the role, while the then-current Robin changed his name and struck out on his own. Damien, the son of Ra's Al Ghul's daughter Talia and Bruce Wayne, became the new Robin at that time, and still is. When Bruce returned, Dick remained Batman for a time, but with 2 Batmans running around, probably won't be much longer.Darkseid seemed to kill Batman, but really just sent him back in time in a effort to use him as a literal time bomb (someon's idea of a pun?). Who would replace him was an issue, but in the end Dick Grayson assumed the role, while the then-current Robin changed his name and struck out on his own. Damien, the son of Ra's Al Ghul's daughter Talia and Bruce Wayne, became the new Robin at that time, and still is. When Bruce returned, Dick remained Batman for a time, but with 2 Batmans running around, probably won't be much longer.It was thought that daksied had killed him however he was sent back in time. Dick became batman until Damien (Bruces son) was old enough and experienced enough to be batman.