JAIF

Chakra = a person's energy.

Even real life people have chakra.

Chakra is just... a word, describing energy.

This changes nothing.

It still isn't determined whether Itachi can surpass the limit of his own strenght within the realm of Tsukuyomi, since the only people he has used it on were much weaker than himself. He may be unable to contain and restrain in the illusionary world a being possessing massive amounts of chakra, Vegito being an example. Until this issue is clarified, any discussion on this subject consists of pure speculation.

As it stands now, the only limit to Tsukuymi is Itachi's amount of chakra. By my calculations, since using Tsukuyomi for three days straight and then for an additional day, and then using Amaterasu drained him off to the point of deactivating even the regular Sharingan (which he keeps on all the time, meaning the drain in chakra is so insignificant it is instantly replenished), he should be able to keep on the illusion for six days straight, meaning six days of torture. Of course, we have no evidence as to whether the type of torture he submits his opponents two affects the chakra drain, so again, any discussion here is speculation.

Theoretically, someone with great control over his senses and the corresponding physical ability could be able to resist being tortured for that amount of time. However, we are not sure how exactly Tsukuyomi takes effect, since even though the pain and the wounds are illusionary, even after the illusion breaks they still take effect. So... again, it's pretty much pure assumptions.

As far as the Amaterasu issue is concerned. Unlike Tsukuyomi, Amaterasu produces externalized results. Someone who is a billion times faster than Itachi could evade the attack even from point-blank, if he had... any kind of idea what was coming at him. Then again, DBZ characters have absolutely no inherent knowledge of Naruto techniques, so Itachi could easily trick the enemy with a Kage Bunshin, have him... talk, or something, then just vanish with Shunshin no Jutsu and reappear behind him, using Amaterasu.

Amaterasu's heat is debatable - the databooks state that it approaches the heat of the sun, but the sun's temperature fluctuates wildly. Also, if you think of applying even a fraction of real-world logic to this, which is required for any crossover matchup to... make sense, do you have any idea what kind of effect bringing the temperature of the sun, even for an instant, even for such a contained impact, would have? It would basically be the heat of a nuclear explosion's core or higher, which would incinerate... everything nearby, evaporate it completely, regardless of the point of impact.

But whatever. Everyone seems stuck to their own opinions. If you fail to realize that until further information is revealed, this discussion will only consist of a series of countless speculations, then I've just wasted my time for nothing.

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