Board Thread:Theories and Speculation/@comment-25122992-20170307224943/@comment-25122992-20170308110857

Regarding Edo Tensei, I think it's pretty hard to strictly follow these rules. Firstly, it's a great temptation for the user not to try and summon a more powerful shinobi. Secondly, it seems that a complete control over the reanimations has its downside too, they become much less effective since they possess a better knowledge how to use their own abilities than the user himself (Hashi/Tobi demonstrated only a fraction of their actual power during their first reamination when Oro controlled them directly). Thirdly, it's impossible to guess which reanimation could know the seals and which couldn't. In addition, unpredictable factors like Kotoamatsukami.

Also, I had an idea that in terms of the battle utility, Rasengan could potentially becomethe strongest technique if used by someone with all the 5 natures mastery or possibly some KKG users. I mean, it's technically posssible to add any nature in existence in Rasengan, thus its possible varians could counter any elemental technique if the user applies an opposite nature or even the same nature (Rasengan with an element is already an S-rank jutsu, if it doesn't overwhelm the enemy's technique, it'd at least nulify it). As demonstrated by Boruto, Rasengan with a certain nature isn't limited by one form, it's possible to create different modifications with the same element. And shape transformation techniques also would be countered as Rasengan is already the highest level of it, let alone with chakra nature.