In the past, Hyogoro was respected by countless samurais, Yakuzas, and even Kaido and Orochi themselves for his legendary strength. However, due to long term malnutrition on account of his imprisonment, along with the effects of old age, Hyogoro’s strength has significantly declined.
Hyogoro is one big metaphor for Wano.
Once before, he and the land stood strong, bountiful and proud.
They would later be seized by Kaido and his pirates. Hyogoro as a prisoner, and Wano as Kaido’s base of operations/territory.
They are shells of their former selves due to the abusive treatment by those who conquered them via deceit and manipulation.
It was intentional for Luffy to encourage Hyogoro, as it’s essentially Luffy inspiring Wano itself to rise up from its predicament. To restore what has been lost, and birth something new. Likewise, Hyogoro teaches Luffy his techniques; Wano joining its hands with Luffy, who can’t beat the enemies controlling it alone.
Now in Chapter 1006, Hyogoro has been infected by the Ice-Oni, which allowed him to return to his prime for a bit. A sign that Wano itself has a fighting chance.
However, he will become a mindless monster that will strike anyone down indiscriminately if they can’t cure him. Kaido plans to drop Onigashima onto the Flower Capital, turning the country into a lawless land of violence, unless the Alliance prevents it. There’s a ticking time bomb factor in both scenarios.
Hyogoro lays it on thick on the meaning of this battle.
We’ve had several emphasis on the coming dawn, through Toki’s prophecy, Yamato’s hopes in Momonosuke, Pedro sacrificing himself, and the fact that the battle is being waged during the night.
The hour of the tiger occurs around sunrise. The tiger being the dragon’s natural foe in Eastern mythology. The current enemy is a dragon, and his defeat timing perfectly with the emerging light is the kind of subtext-to-text practice Oda likes to employ. Remember Sky Island? Cricket wanted to prove the existence of the City of Gold. How did Luffy do it? By ringing the bell that was referred to as the “Light of Shandora,” the light of the Golden City, proving its existence in the most literal fashion.
The next time the sun shines over Wano is when it is free, just as Hyogoro will be.
*Theory by KiriNigiri