Would akainu use a magma sword in that situation ? I very much doubt it.
Well yes , i doubt Akainu would resort to Swordsmanship . maybe Oda wanted to highlight Kizaru's versatility still
Anyway , i still don't believe Kizaru is a Swordsman , when most of the time he didn't even fight with a Sword , it was only against Rayleigh ( a Swordsman , and a super strong one at that ) that he decided to resort to Swordsmanship
In the entire MF he didn't use Murakumo . in Sabaody before Rayleigh he didn't either
Overall i view him as a versatile fighter , who has sword skills . but not a Swordsman , he doesn't even carry a Sword and fights without it most of the time , even against Whitebeard and Marco
In a serious prolonged fight against Awakened Akainu or Awakened Aokiji for example , i doubt he'll use a Sword , just like he didn't against WB and Marco . i think he'll utilize his piercing/explosive Light attacks more , it'll be interesting to see what his Awakened attacks , but i doubt they will be related to Sword when Kizaru isn't portrayed as a Swordsman , but as a versatile fighter who can use a Sword
His strongest attack to date aren't even coming from Murakumo either . it's Yasakani No Magatama , heck
his regular finger and leg explosive light beams could be more powerful than his sword attacks
If he will fight against a Swordsman like Mihawk he may try to utilize Ama No Murakumo again , but i doubt he can match Mihawk's higher end sword attacks with it , so in the end he'll have to resort to his explosive/piercing Light attacks again
In the end , Kizaru def isn't a Swordsman for me .
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Edit - what i meant by the
bolded above , is light beams that can generate explosions like this