Board Thread:Theories and Speculation/@comment-31661816-20170403165339/@comment-681696-20170404150353

The one ANBU stated that the barrier can only be broken from the inside and another stated that if the third took out one of the sound four they could join the fight and said Damn when the sound four created the second barrier.

I personally take was the ANBU said about Shishienjin as being correct and that the ways Naruto fans figure out to stop shishienjin wouldn't work and that they wanted to join the fight to help the Third.