Shiryu wasn’t impressive against Garp. He won’t defeat Benn Beckman with a sneak attack. If he stays how he is, Zoro vs Shiryu won’t be exciting. The other First Mates of Emperors all had a special power. Marco the first Mythical Zoan we have seen. Katakuri had Future Sight. King becomes almost invincible temporarily, while his captain was regarded as unkillable all the time. Crocodile, the closest to an Emperor in paradise, also had a First Mate with superhuman tenacity. Crocodile couldn’t be touched without Haki and water, Mister 1 could only be cut by very advanced swordsmen.
Blackbeard will acquire a Zoan. Shiryu should get one too. The boss will have 3 devil fruits, the First Mate should have 2, to set him apart from the other Titanic Captains. Shiryu can’t eat more than one, so he should put it into his sword. We have yet to see a strong character utilize a devil fruit weapon. One Piece can’t end with only Mister 4 and Spandam wielding such weapons. Oda once said, Zoro would have one of his swords eat Kaido’s Dragon fruit, were he to ever get a devil fruit. Won’t happen, but Oda has the dragon fruit in his mind. He will put it on paper.
Some think Kaido died. I doubt it, Luffy would have killed him. He somehow survived and is now in a weakened state. Someone will take his life. In the past, I have made the case for Shiryu ending him. It is in his name: Shi means death, Ryu means dragon. Zoro is the biological descendant of Ryuma. Shiryu would inherit Ryuma’s legacy by slaying a dragon, one that had Wano in its grip for so long. When Kaido’s life ends, his devil fruit will respawn and Shiryu will put it into his sword. A living Dragon sword may move like Ohm’s iron whip, in Skypiea.
*by milluki