Suggested by iKnowledge All right so if power wasn’t enough to stop Isshiki Ōtsutsuki then how about speed? Reverse Flash has certainly got a whole lot of that after all. Well, he may be able to dodge some attacks but when it comes to combat speed I would say Isshiki has the edge here. His abilities also have a very wide range of attack so that will make dodging them even tougher for the Reverse Flash. Ultimately I’m not convinced that he would be able to do more than briefly put up a fight. Isshiki Ōtsutsuki wins.
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Given how Thawne is fighting people who are close to him in power and given the Speed Force’s range compared to what existing speeds we know about, I wouldn’t count out Reverse-Flash. My defense will rest after this: https://vsbattles.fandom.com/wiki/Professor_Zoom_(Post-Crisis).
For sure he’s a very fast fighter but I don’t see him being able to do a whole lot against someone like Isshiki. Isshiki’s power is just absolutely nuts, even Naruto was unable to outspeed him in his chakra cloak mode
Reverse Flash is equally fast to Flash who has INFINITE SPEED feats. For example, Wally broke the CONCEPT of SPEED ITSELF BY RUNNING. Reverse Flash can fully control time in any way he wants, he is a living paradox, therefore COMPLETELY IMMORTAL, to the point a GOD like Dr. Manhattan, who toys with multiverses couldn’t erase him. His race with the Flash almost COLLAPSED THE MULTIVERSE.
Reverse Flash can NEGATE durability, since he can bypass through atoms and molecules easily with his speed, so even if someone is more durable than the Big Bang itself, he can still kill them. He can do infinite mass punch like the flash where he can increase his Attack Potential INFINITELY with his speed, which is infinite. Speed is relative to mass which is relative to what strength depends on, hence he can increase his attack by an immeasurable fold. There is absolutely nothing Isshiki Otsutsuki can do against Thawne.
Naruto does not even come close to Flash or Reverse Flash in speed, so your argument is really weak.
I would argue that Naruto has better combat speed feats than Flash