Hidan is immortal as long as his secret is not revealed.
That is why Kishi didnt let Byakugan user to vs Hidan or Sasori.
If Kishi let Byakugan user vs Sasori with help from Chiyo then the fight would ended right away. Since Byakugan user can see where the wave of chakra coming from.
Just like Hidan also has chakra like everyone else and it can be detected.
Also Sasori chest piece can control the puppet as it was a real human - since Sasori puppet is made out of Human flesh. This is the only logic in NV that allow us to think that Hidan body is just a puppet that made out of human flesh which is Hidan own body and his real soul (or chest piece like Sasori) is laying somewhere to control the body. It can even be in realm of where Jashin live but still has chakra link to the body.
Before some retard that has 0 knowlegde of NV try to say BS about my theory is not legit. Everything i have say until now has happened before in NV and i just link those event together. If you dont agree then give some real argument how it is not possible, why i am wrong and based on what. If you just spouting out something irrevelant or bs then just get lost
