Sigh...my old Shanks Fanboyism comes again.
One of the reasons i like him so much is his role in the narrative. Being Luffy's spark of inspiration, his absurdly peaceful (or passive? A long-term strategy? A hidden enigmatic purpose?) stance for an Emperor which raise up questions, his relationship to Sengoku (Marines), even him having political position alongside (or against?) Gorosei themselves, and of course his cold enmity with Blackbeard which may get finality in upcoming future.
As if it's not enough, Shanks also has extreme individual power moments. Shanks is the very first man who showed us The Conqueror's Walk in Moby Dick. Then, the first Skysplitter Dance together with WSM. The next moment, he preached while showing Akainu being affected by his basic Conqueror Blast, an utterly impossible situation that Oda portrayed in SBS as the reflection of strength difference. He is also stated by WSC himself as the only person left in the world capable of matching him.
But even his power moments are not complete without the small nuances about him, which is his expression. Shanks is always very expressive. His face is always clear, whether he becomes idiotically unaware or surprised, clumsy, in the mood for party, getting annoyed by a challenger, and it's also clear...whenever he's getting all enigmatic in his preparation, planning and manuvers.
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That's why i like Shanks so much more compared to Mihawk, The World's Strongest Swordsman who is all about manner and being calm, composed, model-like, and obviously strong but...rather bland characteristically and narratively in comparison.