It would appear that Sora is, indeed, the stronger of the two.
Despite protest that Riku is more 'muscled' then Sora, one must note that Sora has shown himself to be able to cut through entire buildings duing his fight with Xemnas, be able to use powerful types of magic, defeat powerful foes such as Cloud, Tifa, Yuffie, and Leon on his own, along with Sephiroth singlehandedly, defeat incredibly powerful opponents, even gods for instance (Hades and Chernabog), and many other strange, thought-impossible, and incredible feats throughout his adventures.
My guess is that, while it is unlikely that they will fight with the intent to kill the other after the KH2 ending, Sora would the victor over the two. 'Bigger muscles' don't mean squat in anime, manga, or Japanese games.
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I think that they both are pretty equal. Sora is the keyblade wielder, but that is only because he chose light over darkness. But Riku couldn't beat Roxas without Ansem, and Roxas is part Sora. In Kingdom Hearts 1 when they were kids Riku always won, but Sora gained so much power during his journeys as well as Riku. I'm going with Sora.
I'm a different person from the one who first submitted the above answer, but I think Riku is stronger than Sora. In Kingdom Hearts CoM (Chain of Memories) Riku's jump is higher, he is faster, and he defeats his enemies more easily than Sora. Yes, Sora has gotten stronger throughout the course of the games, but I think that Riku is the stronger one.
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KHCM show that in there default form,Riku is far stronger than Sora.Roxas after a year of of fighting in OXIII was stronger than Riku. Since Roxas combined with Sora afterwards...you can guess that Sora now have Roxas abilities as well. With that Sora is decisively stronger than Riku
Well technically Mickey is the master of the keyblade unlike sora who is just still gaining experience so maybe in a few years Sora might be able to be as powerful as mickey
but the fact is Mickey also gains experience as Sora does so the best chance that mickey is stronger than sora is high
Sora.
NOTE:
Sora defeats Roxas in battle when he is in The World That Never Was.
depnds on what game if it is chain of mermories sora vs .crisis core zack.
zack would win without a doubt
No.
its sora
Well since sora and aqua are very much like each other so they could be if they're at the same age if you know what I've mean.
NO!!!!!!!!!!!!!! sora is the keyblade master so hes stronger and also sora beaten axel in kingdom hearts chain of memories
No she never meets him SPOILER: She never meets him because wen you get the secret ending aqua goes into the darkness to save terra so she is walking to leave the darkness right now .... for now no one knows if sora will meet aqua
Ven, Terra, and Aqua are the three main characters of Birth by Sleep. Terra represents the darkness like Riku, Aqua is like Kairi but equipped with a Keyblade, and Ven is like Sora but looks like Roxas, since Ven and Sora are connected.
aqua homes skillet biscuit or am i telling da truth maybe
i dont know about stronger but he is a whole lot faster and can hit faster too.
WEll kingdom hearts 3d looks like it may have something to do with terra aqua and ventus
superman
ventus looks like roxas aqua has blue hair and is the only lady terra is the tall dark haired guy ventus=sora aqua=kairi terra=riku in a way...
No because kingdom hearts 3 is related to kingdom hearts birth by sleep but Ventus lost his heart in Ventus's secret ending when Ventus gave Sora his heart, Aqua put Ventus into this dome like where Roxas found Sora in it in kingdom hearts 2. Aqua bilt that to make Ventus heal in Aqua's secret ending.