Amelia didn’t wonder how a ten-years-in-Azkaban Bellatrix could have not just killed, but obliterated the same man who had just defeated Bahry? Not that there aren’t answers (say, a Geas-type spell, with a lethal payload to be triggered by Bellatrix).
An “Avada Kedavra” to the back from point-blank range probably would have worked well enough. A blade would have worked too, I suspect.
An “Avada Kedavra” to the back from point-blank range probably would have worked well enough. A blade would have worked too, I suspect.