Wow your name is fitting because that was savage AF <| sep |> we do know wizards fought in medieval wars so they presumably know the effects of armor and shields vs the killing curse . If they worked , wizards would use them in wars in the modern day , but they didn ' t in HP . This , as above with the other user , is reasonable but still an assumption that doesn ' t prove the point . None in HP as far as I know were preparing for a war . They were people running around in modern times in their normal clothes . Were there even available armors in the school ? It seems to be more about the killing curse finding a target . It looks like it in this videoQXuGSas 9 o ? t 36 , it seems to surround him entirely although it doesn ' t always do this which would make me think it ' s more about there being a living target rather than passing through a defense .