Honestly, I believe that Deidara is more of a ninja genius than Sasuke.

Practically all of Sasuke's techniques are borrowed, and he hasn't created his own jutsu. He depends HEAVILY on Kakashi's chidori and Orochimaru's snake techniques. All he's done on his own is form manipulation with chidori and shishi rendan (which he admits was taken mostly from Lee). Moreover, Sasuke uses Orochimaru's curse seal which gives him super strength and super defense and allows him to use seemingly endless chidoris. Sasuke would have lost to Deidara a while ago if he did not have the Curse Seal! This is partly because he wouldn't be able to use so many chidoris and partly because without the wings of his level 2 curse seal, Sasuke would have been killed by the C2 dragon. Also in chapter 311, it is revealed that on top of the curse seal, Sasuke's speed, strength, and chakra have been amplified by forbidden jutsu and drugs, so Sasuke's practically cheating.

Deidara developed his jutsu entirely by himself. He takes great pride in his art as his own. It is very likely that Deidara was not born with the mouths on his hands. This is clear because one of his replacements arms (the whole one) was likely taken from someone else because his arm was gone forever. Deidara would have had to put the mouth on that hand himself, unless they randomly found someone with a mouth on his hand. His clay birds and explosives, C2 dragon, and C4 Garuda are all brilliant techniques and undoubtedly developed by Deidara without the assistance of anyone else. In his flashback, Deidara was revealed to be a ninja that very much preferred to be on his own, alleging to no one. Even more impressive was Deidara's ability to train a normal eye to counter the "great" Sharingan's genjutsu. Deidara is the superior shinobi.

On another note, I've seen people make the claim that Deidara is "the weakest Akatsuki" or that he has "lost too many battles". First of all, his concluded fights (before the Sasuke fight) are as follows: vs Itachi- loss; vs Gaara- win; vs Kakashi and co.- draw; vs Sanbi- win. Also, especially after this fight, no one should believe that Deidara is the weakest Akatsuki (although it is apparent that he is the youngest). He would easily have won against Hidan who was far from the strategist that Deidara is and was ineffective in long range combat. Deidara would have blown him to bits. And now, as Itachi depends heavily on the Sharingan's genjutsu, Deidara may stand a chance against him with his left eye. I'd say that he was one of the strongest of the Akatsuki.

Again, I'll remind you that my argument was not which ninja is stronger, it was that Deidara is the greater ninja genius. Any idiot could tell that a competitor on steroids (in this case Sasuke) has an advantage over someone who worked on his own to gain strength naturally, and that is the sole reason why Sasuke stood a chance. Additionally, Sasuke being able to summon and control Manda with the Sharingan was utterly ridiculous! He couldn't even stand moments before!





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Rest in peace, Deidara, my love. You'll always be one of my very favorite characters of all fandom.