Oda needs to power up Shiryu. Despite him being Teach’s #2,
DFless Shiryu was = Magellan. And Magellan was superior to Jinbe, so DFless Shiryu was superior to Jinbe as well.
X Higher level > DFless Shiryu > Jinbe, that X higher level is top tier. Shiryu is already a top tier the moment he got his DF power.
With DF upgrade and Awakening, Shiryu will be even more powerful.
, he looked worse than Kuzan in the fight against Garp.
Aokiji couldn't damage ''Iron'' Garp until Shiryu weakened him, only then Aokiji clashed him equally.
Then Garp attacks him but Shiryu simply laughs at it.
Thats superior portrayal when Shiryu didn't even use special moves yet, just random stab + random invisibility, no special sword moves or awakening yet.
Shiryu simply looks superior to 3 billion Kid as well;
- Shiryu attacks Garp's ally, Garp uses future sight to stop Shiryu, Garp gets heavy damage and his attack does little damage to Shiryu.
- Kid attacks Shanks's ally, Shanks uses future sight and beats Kid without taking damage.
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I think the BBP could legitimately kill Mihawk, with Shiryu taking Yoru for himself.
Shiryu already has a special sword Raiu. Oda upgrading Shiryu's Raiu blade to permanent black or red blade while killing Mihawk makes more sense.
Shiryu is a battojutsu master, which is lightning speed attacks.
Not heavy and slow attacks like Mihawk's which even PreTS Luffy was dodging those slow heavy attacks.
Mihawk prefers more powerful attacks with Yoru and cuts icebergs while fighting someone like PreTS Luffy, but Mihawk gives up on speed attacks. Mihawk's style is very different than Shiryu's.
Yoru doesn't suit with Shiryu's battojutsu swordsmanship style.