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This technique creates a barrier around a place by placing four "forbidden" (禁, kin) tags in different locations surrounding the place to be protected, a fifth tag on the location to be protected. The tags are placed on flat surfaces, and are connected with the user's chakra. This technique turns the entire range surrounded by the tags into a barrier space, and inside the space, the material's destruction is "forbidden". Using any kind of physical attack to try and destroy something in the barrier is folly, as it will only lead to injury. To cancel this, it is necessary to search for the four tags and tear them off simultaneously. Meaning there must be at least five people on a team to cancel it.
Even if the tags are removed, the user could add a trap that will create perfect copies of those who have removed the seal, preventing them from returning immediately.