God's Eyes
It's not only because of Chibaku Tensei, but it's also because the Rinnegan users, who can bring out chakra rods can paralyze the bodies (like Madara did to Hashirama & Tobirama).
I don't know for sure if all Rinnegan users can do that trick, but as far as I know, Nagato did the same to Jiraiya in that toad's stomach when Pa had to pull it out of his arm and chest.
What I want to make clear is that a (strong & fast) Rinnegan user can defeat Edo Tensei, even without a Sealing jutsu, and even without Chibaku Tensei.
It's not only because of Chibaku Tensei, but it's also because the Rinnegan users, who can bring out chakra rods can paralyze the bodies (like Madara did to Hashirama & Tobirama).
I don't know for sure if all Rinnegan users can do that trick, but as far as I know, Nagato did the same to Jiraiya in that toad's stomach when Pa had to pull it out of his arm and chest.
What I want to make clear is that a (strong & fast) Rinnegan user can defeat Edo Tensei, even without a Sealing jutsu, and even without Chibaku Tensei.
Every jutsu has a weakness.
-Itachi