Board Thread:Versus Debates/@comment-35057921-20191023205948/@comment-32440156-20191027194011

Umm... because you know, immortality doesn't actually actually make you invincible. She can still be sealed and being a living captive while five chakra rods are embedded in you is not actually nice, just ask the ten-tailed pet of jigen. Zetsu is needed in case she is sealed.

Once again, the laws of chakra are only applicable to a mortal and not an immortal being. Since even Hagoromo stated that she isn't really a "self proclaimed immortal".