yes so he would use that aganist kisame
No, Kisame knows the silent killing technique for one, also Samehada can sense chakra
and yes all the seven swordsman are said to be masters of it
As the name suggests, this technique is simply a very quiet method of killing an opponent, usually from behind with a blade. Additionally, because the user is very silent, it cannot be defended against. The user will often slit their opponent's throat, preventing any cry that might give them away. The Seven Ninja Swordsmen of the Mist are said to be masters of this technique, and were even good enough to track and kill opponents through sound alone.
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