1) Because there are also variations of other jutsus too. For example, if the opponent sent a horizontal whirlwind towards you, you couldn't defend with a vertical version, as it would just cut/pass through it. That's why there are horitontal and vertical techniques, and when defending, you are trying to match the opposing jutsu, most of the time. Kenjutsu, for example, is the opposite. If the opponent attacks you horizontally, you place your sword vertically, in order to block it. Hope you get the point.Only question about the 1st is:
Why are there so many variations of this jutsu, since there is the previous jutsu? are they supposed to be more focused, given they are aiming in only one direction?
Second jutsu:
what is the size of the tornado? would it affect a giant summon of the size of Gamabunta?
2) Nah, I wouldn't say so. It says "minor" in the description, and according to this picture, it's just slightly bigger than an average human, enough to envelop him and do its job.
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