I find that we must deny Itachi's power, because it doesn't make sense for him to be as strong as his feats would indicate that he might be. There are some very simple implications in the manga that should be ignored, or rationalized to be less... even though we haven't seen Itachi, when using his full power, truly be pushed by an opponent to this date, as nobody has beat him, or even scratched him, unless he intended to lose.
Physical Speed
Itachi flash-stepped without Kirābī noticing, even though Kirābī was focused and on his guard, until Nagato shouted "heads up!" Itachi would later flash behind Kirābī and warn him himself. Kirābī was shown to be above Ē's skill level in movement and reaction, as he saved Ē twice from Minato's Hiraishin, and intercepted Ē's assault on Naruto. Itachi doing this to Kirābī would suggest that his speed is closer to Minato than... it is.
Jutsu Speed
Itachi combined his physical speed and jutsu speed to instantly blind Rinnegan shared vision while also activating Susano'o to cut off Nagato's arm, grab both Kirābī and Naruto, and dash backwards before anybody reacted. Itachi's Amaterasu speed seemed, likewise, faster than Naruto could react to on the Cerberus, or Nagato on his bird, nor did Nagato seem to perceive the speed of Itachi using his bankai. Yet this is all... misleading.
Genjutsu
Genjutsu has been hyped to be Itachi's specialty, and Tsukuyomi his magnum opus. We know that Kakashi, even with the Mangekyō Sharingan, learned and used Gai's style of reading body movements to avoid Itachi's genjutsu. We also know that Itachi easily defeated Deidara and Orochimaru without using his Mangekyō Sharingan to strengthen his genjutsu, and defeated Naruto (after defeating Akatsuki) with his summon's base genjutsu. Yet...
Intelligence
This is the most important power of them all, as intelligence is why Shikamaru can defeat ninja that are faster, stronger, and with better jutsu than himself. Itachi has proven himself to be the cleverest shinobi in battle by instantly analyzing and defeating shared vision, Chibaku Tensei, and being the only ninja (Tobi, Hiruzen, Alliance) in the entire world to figure out how to safely defeat Edo Tensei. However, this shouldn't be...
Physical Speed
You must be registered for see images
Itachi flash-stepped without Kirābī noticing, even though Kirābī was focused and on his guard, until Nagato shouted "heads up!" Itachi would later flash behind Kirābī and warn him himself. Kirābī was shown to be above Ē's skill level in movement and reaction, as he saved Ē twice from Minato's Hiraishin, and intercepted Ē's assault on Naruto. Itachi doing this to Kirābī would suggest that his speed is closer to Minato than... it is.
Jutsu Speed
You must be registered for see images
Itachi combined his physical speed and jutsu speed to instantly blind Rinnegan shared vision while also activating Susano'o to cut off Nagato's arm, grab both Kirābī and Naruto, and dash backwards before anybody reacted. Itachi's Amaterasu speed seemed, likewise, faster than Naruto could react to on the Cerberus, or Nagato on his bird, nor did Nagato seem to perceive the speed of Itachi using his bankai. Yet this is all... misleading.
Genjutsu
You must be registered for see images
Genjutsu has been hyped to be Itachi's specialty, and Tsukuyomi his magnum opus. We know that Kakashi, even with the Mangekyō Sharingan, learned and used Gai's style of reading body movements to avoid Itachi's genjutsu. We also know that Itachi easily defeated Deidara and Orochimaru without using his Mangekyō Sharingan to strengthen his genjutsu, and defeated Naruto (after defeating Akatsuki) with his summon's base genjutsu. Yet...
Intelligence
You must be registered for see images
This is the most important power of them all, as intelligence is why Shikamaru can defeat ninja that are faster, stronger, and with better jutsu than himself. Itachi has proven himself to be the cleverest shinobi in battle by instantly analyzing and defeating shared vision, Chibaku Tensei, and being the only ninja (Tobi, Hiruzen, Alliance) in the entire world to figure out how to safely defeat Edo Tensei. However, this shouldn't be...
