Again? What do you mean again?
(as far as he knows, this is the first time. or second actually, if they count that alternate him who died but that gets confusing if you think too hard about it.)
Other options:
no subject
Again? What do you mean again?
(as far as he knows, this is the first time. or second actually, if they count that alternate him who died but that gets confusing if you think too hard about it.)