The 5 Seal Barrier is introduced on the Naruto Shippuuden 18. Kakashi and Chiyo-Baasama realized by looking at the mark as shown below:

It is used to protect the barrier of the cave where the Akatsuki did the extraction of the one-tailed Shukaku from Gaara-Sama’s body. In other words, as long as the 5 Seal Barrier is there to protect the main barrier of the cave, no one from the outside can enter the cave and they can’t even break the main barrier of the entrance of the cave.

Even the powerful punch of Konoha’s Green Beast Gai-Sensie couldn’t break the barrier.

Now, What’s 5 Seal Barrier anyway?

According to Kakashi’s explanation, the 5-Seal Barrier is a barrier made by placing 5 “Forbidden” seals in different places.

In Naruto Shippuuden Anime episode 18, one Forbidden Seal is placed on the main barrier of the entrance of the cave.

In removing the 5 Seal Barrier, all 5 Forbidden Seals should be removed at the same time, or else the barrier will never be removed. The other 4 Forbidden Seals are placed on the following details according to the Byakugan of Neji-Kun:

1- On top of boulder, 500 meters northeast from the main entrance of the cave.
2- On the trunk of a tree, 350 meters southeast from the main entrance of the cave.
3- On the cliff, 600 meters northwest from the main entrance of the cave.
4- In the forest, almost 800 meters southwest from the main entrance of the cave.

However, there’s a trap waiting for the four shinobi who will remove these 5 seals. Those who will remove the Forbidden Seal placed on the main entrance of the cave will face the 2 Akasuki members, namely Sasori and Deidara, waiting for them inside the cave. The other four will face a battle against their own clones that have the same capabilities and abilities as them. The clones will only be defeated if the Akatsuki member who set up the Forbidden 5- Barrier Seals.

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