Board Thread:Naruto Discussions/@comment-34436445-20180703141210/@comment-4271790-20180705183014

Elveonora wrote: Look at it this way, they have rushed over many things that they should have explained. We might get official explanations for some things one day, hopefully. Ahhh, we had hoped the 4th databook would have done that for us but that was a whole ordeal itself... good times (not).

Zen no Sho is a possibility, though.