<p>I don't what the fuss is about to be honest. Just because they don't display them in the manga, doesn't mean they don't have said natures. Kakashi himself stated that almost everyone's chakra falls under at least 1 of the 5 basic natures, so.....
</p><p>And the databooks are classified as canon because they give technique names, explanations on said techniques, and a lot of other information Kishi likely didn't have time (or patience lol) to include in his manga. I'm glad at least the chakra natures aspect was confirmed, and this is coming from the wiki's biggest 4th DB hater. The problem come when the databook information contradicts the manga.
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